Your starting in 3rd gear is a Governor solenoid and/or pressure sensor. I had the same problem with my 04 grand cherokee(42re tranny) and while I was in there I replaced both just as insurance parts cost about 150.00 with fluid and filter. With the 3.9 the 42re and in some cases the 44re was offered you can be sure by looking in your glove box on the sticker it will tell you everything from tranny,transfer case,brakes,paint code axle ratio and so on. The o/d light coming on after driving and not leaving 3rd is a limp mode the computer tells the tranny to do this to prevent and further damage to be done. Im not sure if the solenoid or sensor will cause this problem but it might be call a tranny shop and ask them most will be happy to answer your questions.
HuH? I don't understand what you mean "goes up to 2 1/2 when I first start it and idles down the road"
If you have the 46re transmission with the shift solenoid, the PCM will shift from 1st to 2nd around 2500 rpm, then from 2nd to 3rd around 2200rpm. Once in 3rd gear, it will shift to OD and the rpms will drop down to about 1500rpm as long as you are at low speeds. This is the way my truck shifts. The shifting is done by the PCM as it learns your driving habits. The sensor that determines this shifting is the TSS (Transmission speed sensor or vehicle speed sensor) located on the transmission.
1987 dodge dakota 3.9 v6 automatic 2wd . tranny started rattling and vibrating without any type of indication. any ideas as to what is causing this would be appreciated
1987? Maybe the u-joints on the driveshaft are gone? These don't have grease fittings, so in time (24 yrs), you have to figure that the U-joints have served you well, if it's just starting to vibrate now.
Don't leave it that way for very long, as that vibration is hard on the tranny and it could result in some expensive transmission repairs! If it was mine, I would have them replaced ASAP.
Hello, I have no idea whats wrong but when I first start my truck when its cold it seems to have no presure in the transmision for about 30 seconds and then it finally grabs and from their it runs and shifts fine... no trouble codes yet... anyone no possible solution to this issue??? its a 05 Dakota 4.7l v8 qaud cab 2 wheel drive... has 60,000 miles runs strong just the initial stall till it ingages.. I thank Anyone that has any knowledge bout it....
Not sure what transmission type your truck is using but the way the Chrysler automatics work is that in Park, the torque convertor is not completely filled. Once you start it up and shift into Neutral, the transmission fluid pump (running with the engine idleing) will fill up the torque converter so that when you switch to Drive, the torque convertor is operational. That is why you should always check fluid level on Chrysler transmissions in Neutral, not Park.
There is a drainback valve located in the transmission line next to the radiator that prevents fluid drainback when the vehicle is parked for a lengthy time. Maybe it's blocked and restricting fluid flow to the pressure pump in the transmission.
The other thing is that it takes a second or two, to build up the pressure in the govenor pressure solenoid/regulator valve on the transmission control body to allow the PCM to shift for you. There is a fluid pressure sensor in the govenor regulator transmission that feeds back pressure information to the PCM to allow shifting. There is also a temperature sensor that tells the PCM when the correct transmission temperature is reached (thermistor) for overdrive operation, but this shouldn't affect the lower gear shifts.
Auto transmissions are very complicated, so it's hard to zero in on what the problem may be in your case, as there may be a simple cause for the delay in your case. Inside the transmission control valve body there are 1-2 , 2-3 and 3-4 (overdrive) shift valves, as well as the planetary gear set and a forward and rear clutch and bands that control shifting. Correct fluid pressure is required for these to function in normal operation.
I've got a 92 Dakota with 177K miles that just stared doing this almost exactly as you describe your issue. At first it would rectify itself after a couple of minutes but now it continues until I come to a complete stop. Did you ever find an answer?
So a year goes by and it is up to 90,000 miles. So I go to the shop and ask them to do an oil change and replace the transmission and the rear deferential fluids. So I get it back and I notice that it is running poorly. It will race up in RPM, then dies. During acceleration it will race before it shifts gears. While slowing down to a stop light it will die. This goes on for a week before I take it back to the shop. They take it for a test drive and yea we see what you‘re talking about, but no not sure why. So they have it for an entire day testing it. They open the transmission, no problems there, they test the accelerator switch. They check the computer, no codes, they call a transmission expert. They reset the computer to factory. I drive it for a week, it is better, but now it will not hold a steady speed on the freeway. It keeps arguing with who is in charge, fighting itself. So back to the shop for another day of testing. This goes on for several more weeks. So one day, late in the day they call me at home, they have a driver on the way over to pick me up. It is fixed. So I get to the shop and the owner greets me in the parking lot with the lead mechanic. They were real close to pulling the transmission when they decided to go back into the computer programming. They had remembered that the fuel rail had low fuel pressure when the car was off. The bad check valve on the fuel pump problem had never been replaced. They tweaked the programming to tell it that it was ok to have low fuel when the car was off. It runs great now! So the computer does not like low fuel pressure when the car is off. ! And resetting the computer will erase what it has learned about the other systems.
The hard shifting sounds like the same problem I had. No computer codes until after a few weeks, finally I got the transmission related P7xx series code come up and it was the TSS (transmission speed sensor or OSS Output speed sensor) P-0722, that was causing the high rpm/hard shift problem. I had the transmission speed sensor replaced and shifting returned back to normal. No re-programming was necessary as the PCM relearns the shift points from your driving habits.
As far as the low fuel pressure, that will drop off over time when the truck is sitting there overnight, but as soon as you turn the the key on and the fuel pump relay operates, the fuel rail should be pressurized to 45psi within one second, before starting, so that part doesn't make any sense to me. I use a aftermarket fuel pressure guage to check my fuel rail occasionally and it maintains pressure for a long time with the ignition off.
Having problem with automatic transmission. daughter starts truck up cold, goes about approx half mile.stops at traffic light, then truck start shifting only at low speed. , rpm revs up to approx 400 rpm, but will not hardly move. goes about 20 mph. this dont happen all the time. can truck transmission be tested electrically? any ideas. can regular automotive shop check this out, or do i need to take it to transmission specialist?
Do you mean rev up to 4000 rpm? At 400 rpm it is below normal idle rpm for an automatic and it will hardly move at that rpm. If it revs up to 4000 rpm and is only going 20mph, it appears not to be shifting out of 1st gear.
It depends on several factors: mileage, when transmission was last serviced etc.. a 2002 is 9 years old and requires fluid/filter/adjustment service every 3 or 4 years.
There are 3 sensors and and 3 electrical solenoids operated by the PCM in the transmission. There is also a throttle position sensor that feeds back information to the PCM to help it determine parameters for shift points as well as a transmission speed sensor.
These can be scanned by a DRB scan tool which most dealers have, to see if any faults occur. (Transmission shops may also have the DRB scan tool. )
Also, most electrical failures in the sensors, or transmission control solenoids may bring on a "check engine" light, that can be scanned by any OBDII scan tool, which most owners can afford, or have read by someone with one of these.
Mechanically the transmission is complex, with 2 planetary gear sets and a system of clutches (front/rear, overriding and direct) as well as bands (front/rear) to operate these for gear shifting.
These require proper fluid pressure in the control valve body to operate bands and servos that facilitate the shift points under control of the PCM.
So it depends on where the problem lies, when the transmission is placed in D and the engine rpm and transmission pump fluid pressure inside the transmission determines when gear shifting occurs 1-> 2 upshift point.....or 2->3 upshift point or 3->4 upshift point (when the over drive unit kicks in).
Proper shifting requires proper operation of each section of the transmission responsible for the gear change, be it an automatic upshift or downshift.
Here's a simple test. Does manual shifting from 1->2 or 2- D work?
If so that will provide a clue of which parts may be still operating and which parts under automatic or PCM control or not.
Thankyou for advice.mileage is 97.000.dont knoe when transmission was serviced last.bought from private owner bout 8 months ago.Brang to walts trams shop.Told me we would have to drop pan and inspect transmission for contamination. called back and said yes , their is. would cost 1.300 to replace transmission. or he could replace sensors and solenoid for 300.00 but could not guarentee it would fix problem. said could last just around the corner when driving, or could last six months.so i told him to just put it back together for 75.00. daughter could not effort it at the time. do you think i should i get 2nd opinion? Thanks again for all your help. dpezfive.
I have a 2006 Dakota 4.7L 4X4 with under 50,000 miles. For the Last couple of months the transmission overheat idiot light coms on intermittantly. Ther is no rhyme or reason behind it. Then the light does come on, the transmission starts shifting hard, and the engine will runn a little rough. It will only stay on for a couple of minutes, then the tranny is fine.
It will come on both with in minutes of starting or after running for a period of time.
Fluid levels have been fine. and the fluid didn't need to be changed.
Well there are no guarantees in life either. (97,000 miles on the truck transmission could also mean a band adjustment, as these like the clutches have material that is prone to wear over time. Nothing you can do if the the clutch material is worn, so some slippage may occur, but the bands (2) can be adjusted, once the pan is dropped.
Throttle body valves sticking is the most common issue if the fluid and filter is not changed at regular intervals and this is something that should be done on a regular (50,000 mile basis or even 40,000 miles). The owners manual gives a schedule for routine maintenance and oil changes on the engine, why would someone ignore a complex mechanism like the auto transmission..I don't know, but if you ignore periodic maintenance on an automatic, sooner or later, you will have some trouble with it.
The last thing that can happen with the Chrysler PCM controlled transmissions, is that there are solenoids and sensors that are controlled by the PCM to determine shift points and these can fail.
The transmission shops usually don't have the time to spare for an accurate diagnosis of what has gone wrong on a transmission with practically 100K miles on it, so he has offered a couple of options.. replace the entire transmission and get some kind of 1 year garantee or replace the electrical components on it (cheaper) and hope that fixes the problem.
Certainly a second opinion is worthwhile, if it was mine, and I knew basically what the symptoms were, I would go with the routine service first (fluid/filter)and have the bands adjusted and perhaps the solenoids replaced at the same time, while the pan was off.
You must mean the transmission temperature sensor light? The Chrysler automatic has two sensors that are related to it.
The first one is a sensor that determines transmission shift pressure and it's output to the PCM will vary depending on the pressure of the fluid available at the shift valves in the control valve body.
The second one is a thermistor type that senses the temperature of the fluid in the transmission to determine proper shift points when components are warmed up. Ie: the transmission will not shift into overdrive (4 gear) until the sensor tells the PCM that the predetermined temperature range has been reached.
Transmission fluid temperature is regulated by the transmission cooler lines (you have two..one going to the transmission cooler tank on the side of the rad and the other coming back from from the rad to the transmission. These help to warm up the transmission fluid transferred from the rad heat and depending on how good your rad is at cooling the engine, keeps the transmission at some predetermined temperature, if the rad is providing adequate cooling.
So in summary: a) It could an actual transmission cooling issue bring on the light, and the rad or the transmission cooler tank needs to be reversed flushed. On the rad/ transmission cooler tank, there is an anti-drainback valve at the fittingof the outlet line that goes back to the torque convertor. (This prevents all the fluid in the tank from draining back to the torque convertor when the engine is not running) and this being a one-way valve, it may be restricted somewhat.
b) it may be the transmission temperature sensor itself, (this is a 5 volt sensor). If it is not functioning properly, the PCM will turn on a check engine light and you should be able to read a code: P-0712 Transmission temp voltage too low (under 1.55v) P-0713 Transmission temp voltage too high (over 3.76 volts)
So obviously, if it is working, the voltage range that the PCM expects to see is between 1.55 to 3.75 volts (In other words, only a spread of 2.2v to determine the transmission temperature).
Heres the background. Bought this 2005 Dakota 4x4 in 2007 with 12,000 miles on it. For the last 4 years (ever since I got it) it will occasionally hang in 1st gear only when it is cold. I can tell when it is going to do this because the rpm at idle is a little too high when it is started. It will then hang in 1st gear for a few hundred feet, then shifts hard into 2nd gear, and it seems fine after that. When it does finally shift into 2nd gear, the doors lock, and the idle returns to normal. This only occurs 2-3 times per month, so it is more of an annoyance than anything else. The truck now has 52,000 miles on it, and has had all regular sheduled maintenance done on time. The tranny fluid was just changed. Any idea what this might be??
Don't know why the door locks are affected by shift from 2-3, as the door locks are controlled by the CTM Central Timer Module.
Normal idle rpm should be around 1,000 when first started and engine/tranny is cold.
The delayed shifts when cold from 1st to 2nd are normally controlled by the PCM with the shift solenoid (also called the variable force valve solenoid). The transmission also has a TCC (torque convertor clutch solenoid) and a 3-4 (overdrive) shift solenoid.
Transmission output shaft rpm is sensed by the TSS sensor, which feeds back to the PCM to determine normal PCM controlled shift points. It may be starting to develop a weird symptom. Had it failed completely, you would get a P-0720 "check engine light"code posted by the PCM. "TSS output too low with vehicle speed above 15 mph".
It's a possibility in your case.
I recently had hard shifting problems with mine, until I finally got that code and changed out the TSS. Shifting rpm returned to normal under PCM control.
I have the same truck as Harleyman (2005 Dakota Quad Cab, 4x4 with 4.7L engine), and mine also hangs in first gear on occasion. It has done that since day one (bought new back in 2005). It only happens maybe 10%-20% of the time; it only occurs right after starting up; and like harleyman said, after the first upshift to 2nd, 3rd, etc it's fine.
Automatics these days are complicated animals because the shifting is electronically controlled by the engine computer, or in the Dakotas, the PCM (powertrain control module).
By hanging in first gear, you must mean a "delayed shift" where the engine rpm on the tach goes way up above the normal 1-2 shift range and finally excessive fluid pressure build up in the transmission pressure governor (which controls the shift valves in the control valve body) forces a hard shift.
It could be that the temperature of the transmission is not reached yet at the beginning because the engine (and transmission) is still cold. A transmission temperature sensor feeds back the temperature range to the PCM, but this may only be needed for 3-4 (overdrive) shifts, I don't know if it is used for 1-2 or 2-3 shifts.
The governor solenoid (PCM controlled shift solenoid on the transmission) the springs involved and the governor pressure sensor all play a critical part in shifting the transmission at the correct engine rpm.
My 2000 Ram shop manual (46re transmission type) states that for delayed or erratic shifts, also harsh at times:
Possiblities: 1. Fluid level too low or too high. ( Fluid level on chrysler automatics needs to be check in NEUTRAL with the parking brake on. In park the torque convertor is not completely filled. It is only when the shift column is moved from P through N to D that the torque convertor fills up completely.) 2. Fluid filter clogged 3. Throttle linkage misadjusted 4. Throttle linkage binding somewhere 5. Gearshift cable/linkage misadjusted 6. Clutch or servo failure (the chrysler transmission has several fluid pressure activated clutches, with two bands. The servos operate the two bands.
7. Governor circuit electrical fault (Governor pressure solenoid) 8. Front band misadjusted 9. Transmission fluid pump suction passage leak This last one would be indicated by foam on the transmission dipstick
So as you can see, there are just too many things that can cause delayed or erratic shifting,
The PCM (in it's flash memory) has a stored program of shift points learned from your driving habits. It depends on the the TSS (transmission speed sensor data and governor pressure sensor to determine shift points. It also gets data from the transmission temperature sensor to determine when to shift..but this is a simple thermistor type and rarely if ever goes faulty.
I have a 05 dakota with a automatic V8. I bought it used last year around March. In Nov. I drove to Illinois, Im in south, and noticed on my trip it started down shifting hard from od to 3rd. Once I noticed it I pulled over and checked fluids. They were fine. Then as I proceeded on it would race up in rpms like around 4500 when I would left off the pedal it would down shift HARD. I took it out of od and continued on(I was 8 hours into trip). It was cooler weather and when I topped a hill with cruise on it raised up in rpms again and then when it down shifted at the top of the hill it locked up the rear wheels and threw me into a gaurd rail. Had to leave the truck up north to get the whole drivers side repaired and when I spoke of the tranny they found no codes. Now here it is Oct the next year and I am starting to get the same shift problem again. Today was the first day I noticed it. Any suggestions on why this would only occur during certain months and or the weather? I will admit its scary to drive when it shifts like that back into 3rd. All other gears and such seem great. btw the truck has 100k on it and was last looked over 2 months ago and tech said the fluids in everything look fine.
I have a 1993 Dodge Dakota, 4x4, LE 3.9 eng, 4sp std transmission(w/OD)
I need to know the proper size (tread pitch and length) of the bolts that hold the transmission mounting bracket directly to the transmission. NOT the insulator or tansmission mount bolts.
Just the bolts holding the mounting bracket to the Trans.
That is very strange to have an erratic downshift on top of a hill climb that forced a downshift like that from 0/D to 3rd. With no codes available and the truck disabled and the diagnostic connector hooked up afterwards, any codes that might have been there maybe were gone?
The only thing I can think of on that kind of hard downshift from o/D to 3rd is that the transmission temperature sensor reported a high temperature condition in the transmission and the PCM forced a downshift on you automatically. This will happen if the temperature exceeds 260F (126C) and the the PCM forces the downshift to engage the convertor clutch and the rpms go up to allow the fan to turn faster to allow more cooling through the rad. The PCM will not allow re-engaging o/D until the temperature goes back down to 230F (110C).
If this occured, then no codes would probably be stored.
I thought it some more about your transmission problem, and there has to be more to this story than what you have described here. The transmission downshifting from O/D to 3rd is a normal occurrance and should not lock up the rear wheels as you have described, causing you to lose control.
The transmission has electro-mechanical as well as pressure controls to facilitate up and down shifting. The upshifting is done by the PCM when the appropriate TRANMISSION RPM, VEHICLE SPEED and transmission pressure regulator sensor feed back information to the PCM to allow it to shift. The shift from 3rd to 4th (O/D) is controlled entirely by the PCM, but you send in a manual request (via the O/D switch on the stalk) to disable O/D and if you hit it again, enable O/D.
The gear ratios for a 46re automatic transmission are as follows: 1st 2.45 : 1 (engine crankshaft rotates 2.45 times to 1 rotation of the driveshaft). 2nd 1.45 : 1 3rd 1.0 :1 O/D (4th) 0.69:1
In overdrive the crankshaft turns more slowly than the o/p shaft of the transmission in order to lower rpms and save on fuel on Level Roads. Once you start to climb some steep hills, the O/D should be switched off manually, or the PCM may disengage it on you to protect the engine.
This has a lot to do with throttle position, engine rpm and the transmission throttle cable that goes from the throttle body down to the transmission.
If the TPS sensor is malfunctioning or the TSS (transmission speed sensor) is malfunctioning, shifting will be erratic forces hard shifts with engine rpm climbing much higher than normal when the PCM sets the shift points.
For the rear wheels to lock up like that, either there was a temporary malfunction in the throttle position (sensor) or you pressed down on the accelerator so hard that the throttle position cable FORCED the downshifts into 2nd or even 1st gear..if that occurred, then the rear wheels would "lock up" because of the abrupt huge gear ratio change at speed and the engine torque delivered to the rear wheels at the lower gear ratio while the vehicle was still moving forward from the higher gear ratio selected before it happened.
In other words, if you are moving at 60mph and all of a sudden you get an abnormal downshift to 2nd or even 1st..the engine RPM will shoot up to 4500rpm from a normal 1800 to 2200 rpm, and that corresponding horsepower will deliver a solid punch to the driving wheels at a lower gear ratio, causing them to lockup, vehicle skid and loss of control.
I recently had a problom with my dodge dakota that was in first gear and reverse I had no power, it acted like I was pulling a heavy trailer. I took it to a mechanic and they checked the trans, compression, cat, timing, O2 senser and few other thingsand they could not figure it out and gave me my money back. I took it to the dealer and it tured out that the timing chain was streched. My main reason for posting this is to maybe help some so they dont spend 4 days without a car and not being able to work.
You didn't mention the year of your Dakota or the mileage, but yes with older vehicles or high mileage vehicles, the timing chain does stretch and throw off the timing. Even though it's inside the engine, it is a wear and tear item and people don't realize that. The timing chain is very critical to maintaining absolute timing between the valves and the pistons. If the timing chain gets stretched, the engine timing is incorrect for producing the rated power of the engine because the valves are not bring in a fresh charge of fuel-air mixture or allowing the exhaust to be scavenged out by the piston on the exhaust stroke, so less fuel air mixture can be drawn into the cylinder on the INTAKE stroke because the valve opens too early or too late and conversely on the exhaust stroke of the piston where the exhaust valve is opening too soon or too late.
The PCM can only adjust ignition timing a degree or two either way, it cannot compensate for a stretched timing chain where the relationship between each cylinder's intake and exhaust valve and piston position is off. That's why aftermarker ROLLER chains are preferred over the old fashioned link chains.
You have to replace the complete set of crankshaft gear, camshaft gear when using a double link roller timing chain. (These come with the chain).
I have a 2005 Dakota SLT 2 wheel drive with V6 Magnum engine. The first time that it shifts from 1st to 2nd it shifts fine. Then the next, and all other times, it shifts hard. Also, has a little delay between shift. It shifts into 3rd gear fine. The problem is only from 1st to 2nd. Had the filter and fluid change, but this didn't help.
The delay is because it needs to build up fluid pressure in the control valve body to do the hard shift OR the clutch inside the transmission responsible for shifts between 1st and 2nd is worn or doesn't have enough fluid pressure.
What does it do in the manual gear ranges?
Here's what the 2000 Dodger Ram shop manual has to say about it (46re transmission)
Slips in low gear (D) only, but not in manual 1 position.
In D 1st the only two clutches used are: REAR CLUTCH OVERRUNNING CLUTCH
To go to D 2nd, it needs the FRONT BAND and the REAR CLUTCH to function at the correct rpm. The PCM does an electronic shift using a solenoid valve (governor valve) in the transmission electronic control part of the valve body, which is responsible for operating the bands and clutches on the two stage planetary gear sets.
i have a 1991 dodge dakota 3.9 automatic transmission, i was driving one day and the tranny just quit. I changed the filter/fluid and it still wont go into gear. there weren't any metal shavings in the pan so i believe it didnt "go out" I tried rocking the vehicle to see if it would go into gear. It just seems like it's stuck in neutral. I was wondering if the linkage could come loose internally and if so where and how. linkage is intact and working on the outside so thats why i'm wondering about maybe it coming apart on the inside and if so were?
1991 is a very old transmission. Not sure where to begin..but if you are saying that it "just quit on you", there could be a number of possibilties.
a)The transmission fluid (oil) pump inside isn't building up pressure to operate the clutches and bands necessary for gear changes.
b) valve body (the control part of the transmission) has a serious fluid leak internally and possibly one of the shift valves (1-2) or (2-3), park to neutral, neutral to drive, are no longer functioning.
c) Transmission internal damage..could be anything, even if there were no tell tale metal parts showing up in the pan.
What would cause my 2005 Dodge Dakota to have these symptoms? Upon accelerating, at 10 mph, the transmission seems to make a "thunk" noise, I feel a mild jolt, and the shifting hesitates and then grabs. It has consistently been doing this for 2 weeks,and only at 10 mph. A transmission place said no codes came up when tested. They rebuilt the transmission at a huge cost. I just got it back 2 days ago, and the symptoms are coming back, though not as prominent. What could it be??????
If this symptom existed before the transmission was rebuilt, it would appear the problem was not accurately diagnosed. Automatic transmissions will behave in a similar way if the fluid is low. There may be blockage keeping the fluid from flowing. Check the heat exchanger and related hoses.
This is a delayed shift from 1st to 2nd? What is the rpm when the shift finally occurs? And they rebuilt the transmission? What exactly did they do to it?
The Dodge automatic is a complex transmission, with a oil pump, 2 planetary gear sets, a set of clutches, a set of bands and the servos to operate them as well as a valve control body, a pressure governor, variable force solenoid and sensor, and various shift valves inside the valve control body of the transmission, so it's hard to give an answer without observing operation on a hoist and monitoring transmission rpm and fluid pressure at the test ports.
For 1-2 shifting to take place in D, there are several components of the transmission involved.. transmission fluid pump, governor pressure is a variable pressure input to the valve body and is one of the signals that a shift is necessary. Different sets of clutches and bands are operated or released. There is also a TCC (torque convertor clutch solenoid on the valve body, but I don't think this is involved yet, in the 1-2 shifts which involve: 25 to 70psi being available at the valve body 1-2 shift valve, 1-2 shift control valve, 1-2 shift regulator valve. Lockup valve and lockup solenoid lockup timing valve.
If you are experiencing harsh shifts 1-2, or 2-3 or 3-4, it could be attributed to a lockup solenoid malfunction. Did they do pressure test at the test ports on the transmission?
If it's due to a solenoid malfunction which is in the valve body, the pan has to come off and the valve body removed to replace the solenoid assembly.
The transmission shift points are controlled by the PCM based on a appropriate rpm, and transmission fluid pressure feedback to the PCM.
It operates a variable force solenoid, TCC solenoid, and 3-4 shift (O/D solenoid).
The variable force solenoid is operated by the PCM in D when it receives the appropriate transmission output shaft rpm (TSS) sensor and the appropriate pressure in the transmission pressure sensor to facilitate PCM gear shifting for you.
If the PCM shift points are not happening, then fluid pressure will build up and hard shift, (rather than a softer modulated electronic solenoid shift) will occur.
The TSS (transmission speed sensor on the transmission sends transmission output shaft rpm to the PCM which will control the shift program points.
It could also be a sensor or a solenoid acting up and not generating a code. I had a similar harsh shifting problem/high shift rpm until I replaced the TSS. Transmission shifting returned to normal after it was changed, and that was all that was done to my transmission.
I have a 2003 Dodge Dakota SLT Quad cab with the 4.7 V8.
The problem I've been having is when I drive off either first thing in the morning (or whenever the truck has been sitting for about 10 mins or longer) it seems the truck is sluggish driving down the street for a block or two and it makes it sound like the engine is "louder" then usual (compared to when I first got the truck) once I've driven for that amount of distance or so, the louder "engine" sound smooths out to a normal sound and all is good afterwards. This problem persists longer, the longer the truck has sat, or the temperature outside. I thought that maybe I needed the tranny filter changed, did that several months ago, then I decided to get the tranny flushed, and for the hell of it, changed the filter again. (200$)
The first time I had the filter changed I could notice a little bit of difference, it was still doing it, but not as bad, but it progressively got back to where it was again. Just had the tranny flushed and filter changed, but it has made no difference as far as I can tell. The guy who did the tranny flush looked at the fluid and didn't see anything in it showing any catastrophic problems but obviously I need to get the problem fixed, because I'm figuring (I'm no car guy if you haven't figured it out) that its not pumping my tranny fluid right or something and eventually I'm going to have a really really expensive problem. I've noticed other guys on the forums have had their computer's read, I haven't had this done, I have had a engine light on, but the last time I checked it was for a damn gas cap sensor (changed gas cap, still would come on), I guess I should have it checked again.
Sounds like the transmission is staying in 1st longer than it should? Nothing specific to offer, but my 2005 (same engine as yours) does the same thing, but usually only when cold. The tranny operates normally after the first up shift, usually within a block or so.
The louder sound which smooths out, after the truck has travelled a little distance is more than likely the thermostatic viscous clutched fan. It will turn faster initially (when cold)and make more noise, until the viscous fluid decouples the fan from the fan pulley and the fan starts to freewheel.
The only way you can tell if it's an actual transmission problem is watching the RPM at the shift points (1->2) and (2->3) on the tach. If the shift points (set by the PCM) appear to be within a normal range, then more than likely the transmission is shifting gears. If the RPMs shoot way up in 1st gear or 2nd gear, then you would have something to be concerned about.
If that happens you would get hard shifts which are very noticible. In those cases, it's either the TSS (tranmission speed sensor) or possibly the TPS (throttle position sensor).
I have a 2004 Dodge Dakota 4x4 . The transmissions is acting up . Its shifts into higher gears too soon . When under 45 , I have to keep the overdrive off . Sometimes when it does thyere is a little chatter , but seems because the shift was way to early and the engine rpm's are to low . When it does shift tho it is a smooth shift . Any ideas or will this be a complete rebild ?
" Its shifts into higher gears too soon . When under 45 , I have to keep the overdrive off . Sometimes when it does there is a little chatter , but seems because the shift was way to early and the engine rpm's are too low "
By "shift's into higher gears too soon"..I would presume that the PCM electronic shifts are taking place, rather than higher pressure induced "hard shifts" done at higher rpms.
There is a TPS throttle position sensor located on the LEFT (driver's)side of the throttle body. It connects to the throttle shaft (butterfly valves) and feeds back information to the PCM on what the throttle is doing at the time.
The second sensor associated with shifting gears, is the Governor pressor sensor located on the transmission itself. This sensor tells the PCM (computer) what the fluid pressure is in the valve body (the part of the transmission that has the fluid activated shift valves to operate the clutches and bands for the dual planetary gear set and the separate overdrive unit.
The third sensor is the TSS, which tells the PCM the rpm of the o/p shaft of the transmission itself.
The shift program is learned by the PCM from your driving habits and feedback from these sensors..which need to be checked out first before considering an expensive transmission rebuild.
The "chatter" you are referring to..could be the engine "shuddering" because of the higher gear loading on the engine is too much for the rpm and torque of the engine at the time....or an actual internal clutch inside the Dodge transmission chattering because it is slipping on it's friction plates..or low fluid pressure being delivered by the transmission fluid pump.
There are test ports for determining transmission fluid pressure that a transmission shop can do (with the vehicle running on a hoist) to see if it's fluid pressure, or worn clutches...or even a bad sensor.
Generally speaking, the transmission should shift from 1st gear to second gear electronically around 2200 rpm..if everything, including the sensors mentioned are working correctly. Shifting from 2nd to 3rd gear is about the same or slightly lower rpm (1800 to 2000 rpm)
Shifting from 3rd gear to the O/D (4th gear) is around 1800 and then once in O/D,the engine rpm drops down to about 1500..if you are under 50mph. The rpm will increase with speed.
Carverman, I suppose I am not good at explaining. But here today it did it once again. I will try and explain todays actions. It is cludy and 40 degrees today. I left for lunch and got onto the highway and it accelerated to 45 MPH at 3700 rpm. When I released the gas pedal it downshifted and felt like "rear end" locked up. Once again as previously noted it might not have locked the rearend up but thats how it feels. Almost like a chevy drive shaftclanks when u-joints going out. That abript kind of feel. So I gave it the gas again so to not get run over from behind and the RPMs climbed up once again and would only go about 50 mph. It bucked and bronced on me and then the engine light came on. I took it by the Ford house, where I bought it used and the mechanic ran a generic test on it and it showed that the MAF/MAP sensor was faulty. He suggested I go by the Dodge house to have them run a diagnostic test on it. They quoted me(Dodge) 130.00 to test the problem. I did NOT get it done as for it is too close to the holidays and well 130.00 is alot. I stopped by the local Auto Parts store and they pulled a TPS sensor code. I went ahead and bought one since its only 20.00. Have yet to install it.When I got BACK in the truck and headed back to work I noticed the engine light was OFF and then the cruise button stopped working. This also happened last year around the wreck. SO in short I think it may have something to do with the transmission ie the case aluminum may be so cold that something is sticking in it until it reaches a warmer temp?? That is just a educated guess on my end. I DO like the info you gave me and I am sorry I did not explain well enough the last go round. See what this info throws your way.
"accelerated to 45 MPH at 3700 rpm. When I released the gas pedal it downshifted and felt like "rear end" locked up."
3700 rpm is definitely too high for 45mph. It appears that the PCM is no longer involved with shifting the gear ranges, and it's the hydraulic fluid pump pressure building up, operating the shift valves in the transmission's control valve body. The rear end feeling like it is locking up is another indication of ABRUPT SHIFTING taking place..in this case, it could be down to 1st gear ... that is very hard on the transmission components!
The Ford house diagnostic is a red herring. The MAF/MAP sensor is used to adjust the fuel/air ratio by the PCM and nothing to do with your transmission erratic/abrupt shifting problem.
The Auto Parts pulling a TPS sensor code, MAY have something to do with it, but I had a similar case not too long ago..hard shifts and it turned out to be the TSS Transmission output shaft speed sensor ). It had a low o/p and the PCM could not read it, so it decided not to bother shifting for me and all the shifts were HARD shifts at high rpms where the Tach just climbed way up there... before it finally shifted. I bought a new TPS sensor, also thinking it was the cause of the problem. Unfortunately the on-line auto parts place sent me a BAD replacement sensor..so I had to put the original back on and tested it.
BTW you can test the TPS sensor still on the vehicle with a Digital voltmeter back probe the 3 wires on the sensor, ignition on but not started, and move the throttle by hand. A good TPS sensor will read 0.5v to +4.5v.... as these are 5 volt sensors.
In my case there was NOTHING WRONG with my OEM TPS sensor and it is still on my truck shifting properly...my problem turned out to be the TSS (located on the transmission itself) and eventually the sensor " finally died" and I pulled a P-0720 code (Low output speed sensor at RPM above 15mph) "Output shaft speed DETECTED is LESS THAN 60MPH with VEHICLE SPEED MORE THAN 15MPH."
On the electronically shifted Dodge transmissions, the PCM does the shifting at the correct "learned" rpm detected by your driving habits. it uses the input from ALL these following sensors, to calculate and determine the proper gear shift points:
1. gas pedal-throttle valve position (TPS)
2. TSS ( Transmission o/p shaft speed sensor) tells the PCM what gear the transmission is SUPPOSED TO BE IN ALREADY when in Drive)
3. VSS (vehicle speed sensor..located in the rear differential housing) the pulses from this one are used to a)calculate your speed on the speedometer, and b)tell the ABS controller (controller anti-lock rear wheel brakes or all wheel antilock brakes) what is happening with the rpm on the rear differential gears
4. Transmission fluid pressure governor sensor (this sensor feeds back information to the PCM of what the instantaneous internal control shift valve body's fluid pressure is..to determine the correct shift points as well.
5. Transmission temperature sensor (tells the PCM when the transmission is warm enough to go into 4th gear (Overdrive) or when the transmission is overheating..sets the Trans Temp indicator on the dash.
So as you can see there are several electronic sensors involved with shifting the gears electronically/automatically for you on the Dodge 44RE transmission.
BTW (44 RE) 4= (4 WHEEL), 4= (transmission torque handling capability) R=(rear wheel drive) E = (electronically shifted..by the PCM)
Not having a handheld OBDII code reader, you are at the mercy of the "stealerships" to plug in and read off the code(s) for you... at $130 a pop!
If you want to keep the diagnostic costs down, you need the basic owner's tools in your tool kit: 1. A Haynes or Chilton manual for your truck year ($30) 2. A cheap DVM (digital voltmeter) around $15-$25 3. A handheld OBD (on board diagnostics) code reader that will scan the PCM and give you the P-codes (problem codes) when you plug it into the diagnostic connector located under the steering column. These are very easy to use, come with a manual explaining the codes and cost under $60 now.
So for the price of that $130 dealer scan..you can equip yourself with some very capable tools of your own..and learn how to diagnose your truck's problems as time goes on.
AND.. "happened around the time of the wreck" Do you mean this truck was involved in a serious accident last year? Please provide more details on that.
I have a 96 Dakota 4x4 quad cab and its problems started out as the transmission would get hot and wouldn't shift passed 2 gear so I took it to the shop and they said that I needed a new one that rebuilding it would cost more so then the next day I started it up and went to put it in any gear my truck would stall right away what would cause this anyone know?? Please help !!
It's hard to say what would cause the stall. Does it seem to start up ok while in park? When you move it into D..does it drop in rpm first and then stall..or stall immediately as you move the gear shift? Have you tried moving it from park to neutral..what does it do in neutral?
There are many reasons for it to stall..something in the transmission is telling the PCM to operated the ASD (Automatic Shutdown Relay) or the extra load on the engine (in the transmission may be causing it to stall because the gear selection isn't right. )
Are there any check engine codes coming on when it happens?
My 2003 V6 is doing the same thing. Only during a left turn. Fluid level is correct. I'll be calling a few transmission people and see what they have to say.
What indications are there that the transmission is slipping on left turns only? Using that convention, does that mean that the transmission DOES NOT SLIP on right turns or when travelling straight?
It doesn't make a lot of sense, since the engine is driving the torque convertor inside the transmission wheter you go straight or make turns. On a turn the power steering pump works harder to operate the steering box and the steering linkage to turn the wheels, but that shouldn't really have any effect on transmission operation...unless the g-forces in a left turn act on the fluid levels inside the valve body in the transmission in one direction and not the other..
Comments
Thanks
If you have the 46re transmission with the shift solenoid, the PCM
will shift from 1st to 2nd around 2500 rpm, then from 2nd to 3rd around
2200rpm. Once in 3rd gear, it will shift to OD and the rpms will drop down
to about 1500rpm as long as you are at low speeds. This is the way
my truck shifts. The shifting is done by the PCM as it learns your driving
habits. The sensor that determines this shifting is the TSS (Transmission
speed sensor or vehicle speed sensor) located on the transmission.
These don't have grease fittings, so in time (24 yrs), you have to figure that the U-joints have served you well, if it's just starting to vibrate now.
Don't leave it that way for very long, as that vibration is hard on the tranny and it could result in some expensive transmission repairs!
If it was mine, I would have them replaced ASAP.
its a 05 Dakota 4.7l v8 qaud cab 2 wheel drive... has 60,000 miles runs strong just the initial stall till it ingages..
I thank Anyone that has any knowledge bout it....
shift into Neutral, the transmission fluid pump (running with the engine idleing) will fill up
the torque converter so that when you switch to Drive, the torque convertor is operational.
That is why you should always check fluid level on Chrysler transmissions in Neutral, not
Park.
There is a drainback valve located in the transmission line next to the radiator that prevents
fluid drainback when the vehicle is parked for a lengthy time. Maybe it's blocked and restricting
fluid flow to the pressure pump in the transmission.
The other thing is that it takes a second or two, to build up the pressure in the govenor pressure solenoid/regulator valve on the transmission control body to allow the PCM to shift for you.
There is a fluid pressure sensor in the govenor regulator transmission that feeds back
pressure information to the PCM to allow shifting.
There is also a temperature sensor that tells the PCM when the correct transmission temperature is reached (thermistor) for overdrive operation, but this shouldn't affect
the lower gear shifts.
Auto transmissions are very complicated, so it's hard to zero in on what the problem may be
in your case, as there may be a simple cause for the delay in your case.
Inside the transmission control valve body there are 1-2 , 2-3 and 3-4 (overdrive) shift valves, as well as the planetary gear set and a forward and rear clutch and bands that control shifting. Correct fluid pressure is required for these to function in normal operation.
until after a few weeks, finally I got the transmission related P7xx series
code come up and it was the TSS (transmission speed sensor or OSS
Output speed sensor) P-0722, that was causing the high rpm/hard shift problem. I had the transmission speed sensor replaced and shifting
returned back to normal. No re-programming was necessary as the PCM
relearns the shift points from your driving habits.
As far as the low fuel pressure, that will drop off over time when the
truck is sitting there overnight, but as soon as you turn the the key
on and the fuel pump relay operates, the fuel rail should be pressurized
to 45psi within one second, before starting, so that part doesn't
make any sense to me. I use a aftermarket fuel pressure guage to
check my fuel rail occasionally and it maintains pressure for a long time
with the ignition off.
rpm for an automatic and it will hardly move at that rpm.
If it revs up to 4000 rpm and is only going 20mph, it appears not
to be shifting out of 1st gear.
It depends on several factors: mileage, when transmission was last serviced etc..
a 2002 is 9 years old and requires fluid/filter/adjustment service
every 3 or 4 years.
There are 3 sensors and and 3 electrical solenoids operated by the PCM
in the transmission. There is also a throttle position sensor that feeds
back information to the PCM to help it determine parameters for shift
points as well as a transmission speed sensor.
These can be scanned by a DRB scan tool which most dealers have, to see
if any faults occur. (Transmission shops may also have the DRB scan tool. )
Also, most electrical failures in the sensors, or transmission control solenoids may bring on a "check engine" light, that can be scanned by any OBDII scan tool, which most owners can afford,
or have read by someone with one of these.
Mechanically the transmission is complex, with 2 planetary gear sets and
a system of clutches (front/rear, overriding and direct) as well as
bands (front/rear) to operate these for gear shifting.
These require proper fluid pressure in the control valve body to operate
bands and servos that facilitate the shift points under control of the
PCM.
So it depends on where the problem lies, when the transmission is placed
in D and the engine rpm and transmission pump fluid pressure inside
the transmission determines when gear shifting occurs
1-> 2 upshift point.....or 2->3 upshift point or 3->4 upshift point
(when the over drive unit kicks in).
Proper shifting requires proper operation of each section of the transmission
responsible for the gear change, be it an automatic upshift or downshift.
Here's a simple test. Does manual shifting from 1->2 or 2- D work?
If so that will provide a clue of which parts may be still operating and which
parts under automatic or PCM control or not.
It will come on both with in minutes of starting or after running for a period of time.
Fluid levels have been fine. and the fluid didn't need to be changed.
Any ideas?
have material that is prone to wear over time. Nothing you can do if the
the clutch material is worn, so some slippage may occur, but the bands (2)
can be adjusted, once the pan is dropped.
Throttle body valves sticking is the most common issue if the fluid and filter
is not changed at regular intervals and this is something that should be
done on a regular (50,000 mile basis or even 40,000 miles). The owners
manual gives a schedule for routine maintenance and oil changes on the
engine, why would someone ignore a complex mechanism like the
auto transmission..I don't know, but if you ignore periodic maintenance
on an automatic, sooner or later, you will have some trouble with it.
The last thing that can happen with the Chrysler PCM controlled transmissions, is that there are solenoids and sensors that are controlled
by the PCM to determine shift points and these can fail.
The transmission shops usually don't have the time to spare for an accurate
diagnosis of what has gone wrong on a transmission with practically
100K miles on it, so he has offered a couple of options..
replace the entire transmission and get some kind of 1 year garantee
or replace the electrical components on it (cheaper) and hope that
fixes the problem.
Certainly a second opinion is worthwhile, if it was mine, and I knew
basically what the symptoms were, I would go with the routine service
first (fluid/filter)and have the bands adjusted and perhaps the solenoids
replaced at the same time, while the pan was off.
The Chrysler automatic has two sensors that are related to it.
The first one is a sensor that determines transmission shift pressure
and it's output to the PCM will vary depending on the pressure of the
fluid available at the shift valves in the control valve body.
The second one is a thermistor type that senses the temperature of
the fluid in the transmission to determine proper shift points when
components are warmed up. Ie: the transmission will not shift into
overdrive (4 gear) until the sensor tells the PCM that the predetermined
temperature range has been reached.
Transmission fluid temperature is regulated by the transmission cooler lines
(you have two..one going to the transmission cooler tank on the side of the
rad and the other coming back from from the rad to the transmission.
These help to warm up the transmission fluid transferred from the rad heat
and depending on how good your rad is at cooling the engine, keeps the
transmission at some predetermined temperature, if the rad is providing
adequate cooling.
So in summary:
a) It could an actual transmission cooling issue bring on the light, and the rad or the transmission cooler tank needs to be reversed flushed.
On the rad/ transmission cooler tank, there is an anti-drainback
valve at the fittingof the outlet line that goes back to the torque convertor. (This prevents all the fluid in the tank from draining back to the torque convertor when the engine is not running) and this being a one-way valve, it may be restricted somewhat.
b) it may be the transmission temperature sensor itself, (this is a 5 volt
sensor).
If it is not functioning properly, the PCM will turn on a check engine
light and you should be able to read a code:
P-0712 Transmission temp voltage too low (under 1.55v)
P-0713 Transmission temp voltage too high (over 3.76 volts)
So obviously, if it is working, the voltage range that the PCM expects
to see is between 1.55 to 3.75 volts (In other words, only a
spread of 2.2v to determine the transmission temperature).
Normal idle rpm should be around 1,000 when first started and engine/tranny is cold.
The delayed shifts when cold from 1st to 2nd are normally controlled by the PCM with the shift solenoid (also called the variable force valve solenoid). The transmission also has a TCC (torque convertor clutch solenoid) and a 3-4 (overdrive) shift solenoid.
Transmission output shaft rpm is sensed by the TSS sensor, which feeds back to the PCM to determine normal PCM controlled shift points. It may be starting to develop a weird symptom.
Had it failed completely, you would get a P-0720 "check engine light"code
posted by the PCM.
"TSS output too low with vehicle speed above 15 mph".
It's a possibility in your case.
I recently had hard shifting problems with mine, until I finally got that code and changed out the TSS. Shifting rpm returned to normal under
PCM control.
electronically controlled by the engine computer, or in the Dakotas, the
PCM (powertrain control module).
By hanging in first gear, you must mean a "delayed shift" where the engine
rpm on the tach goes way up above the normal 1-2 shift range and finally
excessive fluid pressure build up in the transmission pressure governor
(which controls the shift valves in the control valve body) forces a hard shift.
It could be that the temperature of the transmission is not reached yet
at the beginning because the engine (and transmission) is still cold.
A transmission temperature sensor feeds back the temperature range
to the PCM, but this may only be needed for 3-4 (overdrive) shifts, I
don't know if it is used for 1-2 or 2-3 shifts.
The governor solenoid (PCM controlled shift solenoid on the transmission)
the springs involved and the governor pressure sensor all play a critical
part in shifting the transmission at the correct engine rpm.
My 2000 Ram shop manual (46re transmission type) states that for
delayed or erratic shifts, also harsh at times:
Possiblities:
1. Fluid level too low or too high.
( Fluid level on chrysler automatics needs
to be check in NEUTRAL with the parking brake on. In park the torque
convertor is not completely filled. It is only when the shift column is
moved from P through N to D that the torque convertor fills up completely.)
2. Fluid filter clogged
3. Throttle linkage misadjusted
4. Throttle linkage binding somewhere
5. Gearshift cable/linkage misadjusted
6. Clutch or servo failure
(the chrysler transmission has several fluid pressure activated clutches,
with two bands. The servos operate the two bands.
7. Governor circuit electrical fault (Governor pressure solenoid)
8. Front band misadjusted
9. Transmission fluid pump suction passage leak
This last one would be indicated by foam on the transmission dipstick
So as you can see, there are just too many things that can cause delayed
or erratic shifting,
The PCM (in it's flash memory) has a stored program of shift points learned
from your driving habits. It depends on the the TSS (transmission speed
sensor data and governor pressure sensor to determine shift points.
It also gets data from the transmission temperature sensor to determine
when to shift..but this is a simple thermistor type and rarely if ever goes
faulty.
I need to know the proper size (tread pitch and length) of the bolts that hold the transmission mounting bracket directly to the transmission. NOT the insulator or tansmission mount bolts.
Just the bolts holding the mounting bracket to the Trans.
Thank You.
forced a downshift like that from 0/D to 3rd. With no codes available and
the truck disabled and the diagnostic connector hooked up afterwards,
any codes that might have been there maybe were gone?
The only thing I can think of on that kind of hard downshift from o/D to
3rd is that the transmission temperature sensor reported a high temperature condition in the transmission and the PCM forced a downshift
on you automatically. This will happen if the temperature exceeds 260F
(126C) and the the PCM forces the downshift to engage the convertor clutch
and the rpms go up to allow the fan to turn faster to allow more cooling
through the rad. The PCM will not allow re-engaging o/D until the temperature goes back down to 230F (110C).
If this occured, then no codes would probably be stored.
be more to this story than what you have described here.
The transmission downshifting from O/D to 3rd is a normal occurrance and
should not lock up the rear wheels as you have described, causing you
to lose control.
The transmission has electro-mechanical as well as pressure controls to
facilitate up and down shifting. The upshifting is done by the PCM when
the appropriate TRANMISSION RPM, VEHICLE SPEED and transmission pressure regulator sensor feed back information to the PCM to allow it
to shift. The shift from 3rd to 4th (O/D) is controlled entirely by the
PCM, but you send in a manual request (via the O/D switch on the stalk)
to disable O/D and if you hit it again, enable O/D.
The gear ratios for a 46re automatic transmission are as follows:
1st 2.45 : 1 (engine crankshaft rotates 2.45 times to 1 rotation of
the driveshaft).
2nd 1.45 : 1
3rd 1.0 :1
O/D (4th) 0.69:1
In overdrive the crankshaft turns more slowly than the o/p shaft of
the transmission in order to lower rpms and save on fuel on
Level Roads. Once you start to climb some steep hills, the O/D should
be switched off manually, or the PCM may disengage it on you to protect
the engine.
This has a lot to do with throttle position, engine rpm and the transmission
throttle cable that goes from the throttle body down to the transmission.
If the TPS sensor is malfunctioning or the TSS (transmission speed sensor)
is malfunctioning, shifting will be erratic forces hard shifts with engine
rpm climbing much higher than normal when the PCM sets the shift points.
For the rear wheels to lock up like that, either there was a temporary
malfunction in the throttle position (sensor) or you pressed down on
the accelerator so hard that the throttle position cable FORCED the
downshifts into 2nd or even 1st gear..if that occurred, then the rear
wheels would "lock up" because of the abrupt huge gear ratio change at
speed and the engine torque delivered to the rear wheels at the lower
gear ratio while the vehicle was still moving forward from the higher
gear ratio selected before it happened.
In other words, if you are moving at 60mph and all of a sudden you get
an abnormal downshift to 2nd or even 1st..the engine RPM will shoot up to 4500rpm from a normal 1800 to 2200 rpm, and that corresponding horsepower will deliver a solid punch to the driving wheels at a lower
gear ratio, causing them to lockup, vehicle skid and loss of control.
with older vehicles or high mileage vehicles, the timing chain does
stretch and throw off the timing. Even though it's inside the engine, it
is a wear and tear item and people don't realize that. The timing chain
is very critical to maintaining absolute timing between the valves and
the pistons. If the timing chain gets stretched, the engine timing is
incorrect for producing the rated power of the engine because the
valves are not bring in a fresh charge of fuel-air mixture or allowing
the exhaust to be scavenged out by the piston on the exhaust stroke,
so less fuel air mixture can be drawn into the cylinder on the INTAKE
stroke because the valve opens too early or too late and conversely
on the exhaust stroke of the piston where the exhaust valve is
opening too soon or too late.
The PCM can only adjust ignition timing a degree or two either way, it
cannot compensate for a stretched timing chain where the relationship
between each cylinder's intake and exhaust valve and piston position is
off. That's why aftermarker ROLLER chains are preferred over the old fashioned link chains.
You have to replace the complete set of crankshaft gear, camshaft gear when using a double link roller timing chain. (These come with the chain).
the hard shift OR the clutch inside the transmission responsible for shifts between 1st
and 2nd is worn or doesn't have enough fluid pressure.
What does it do in the manual gear ranges?
Here's what the 2000 Dodger Ram shop manual has to say about it (46re transmission)
Slips in low gear (D) only, but not in manual 1 position.
Overrunning clutch faulty. Replace overrunning clutch.
In D 1st the only two clutches used are:
REAR CLUTCH
OVERRUNNING CLUTCH
To go to D 2nd, it needs the FRONT BAND and the REAR CLUTCH to function at
the correct rpm. The PCM does an electronic shift using a solenoid valve
(governor valve) in the transmission electronic control part of the valve body,
which is responsible for operating the bands and clutches on the two stage
planetary gear sets.
saying that it "just quit on you", there could be a number of possibilties.
a)The transmission fluid (oil) pump inside isn't building up pressure to operate the clutches and bands necessary for gear changes.
b) valve body (the control part of the transmission) has a serious fluid leak
internally and possibly one of the shift valves (1-2) or (2-3), park to neutral, neutral to drive, are no longer functioning.
c) Transmission internal damage..could be anything, even if there were
no tell tale metal parts showing up in the pan.
d) Park/neutral switch on transmission?
Time to take it in and replaced.
finally occurs?
And they rebuilt the transmission? What exactly did they do to it?
The Dodge automatic is a complex transmission, with a oil pump,
2 planetary gear sets, a set of clutches, a set of bands and the servos
to operate them as well as a valve control body, a pressure governor,
variable force solenoid and sensor, and various shift valves inside
the valve control body of the transmission, so it's hard to give an
answer without observing operation on a hoist and monitoring transmission rpm and fluid pressure at the test ports.
For 1-2 shifting to take place in D, there are several components of the
transmission involved..
transmission fluid pump,
governor pressure is a variable pressure input to the valve body and is one
of the signals that a shift is necessary.
Different sets of clutches and bands are operated or released.
There is also a TCC (torque convertor clutch solenoid on the valve body,
but I don't think this is involved yet,
in the 1-2 shifts which involve:
25 to 70psi being available at the valve body
1-2 shift valve, 1-2 shift control valve, 1-2 shift regulator valve.
Lockup valve and lockup solenoid
lockup timing valve.
If you are experiencing harsh shifts 1-2, or 2-3 or 3-4, it could be
attributed to a lockup solenoid malfunction. Did they do pressure test
at the test ports on the transmission?
If it's due to a solenoid malfunction which is in the valve body, the pan
has to come off and the valve body removed to replace the solenoid
assembly.
The transmission shift points are controlled by the PCM based on a
appropriate rpm, and transmission fluid pressure feedback to the PCM.
It operates a variable force solenoid, TCC solenoid, and 3-4 shift (O/D
solenoid).
The variable force solenoid is operated by the PCM in D when it receives
the appropriate transmission output shaft rpm (TSS) sensor and the appropriate pressure in the transmission pressure sensor to facilitate PCM gear shifting for you.
If the PCM shift points are not happening, then fluid pressure
will build up and hard shift, (rather than a softer modulated electronic solenoid shift) will occur.
The TSS (transmission speed sensor on the transmission sends transmission output shaft rpm to the PCM which will control the
shift program points.
It could also be a sensor or a solenoid acting up and not generating a
code. I had a similar harsh shifting problem/high shift rpm until I
replaced the TSS. Transmission shifting returned to normal after
it was changed, and that was all that was done to my transmission.
The problem I've been having is when I drive off either first thing in the morning (or whenever the truck has been sitting for about 10 mins or longer) it seems the truck is sluggish driving down the street for a block or two and it makes it sound like the engine is "louder" then usual (compared to when I first got the truck) once I've driven for that amount of distance or so, the louder "engine" sound smooths out to a normal sound and all is good afterwards. This problem persists longer, the longer the truck has sat, or the temperature outside. I thought that maybe I needed the tranny filter changed, did that several months ago, then I decided to get the tranny flushed, and for the hell of it, changed the filter again. (200$)
The first time I had the filter changed I could notice a little bit of difference, it was still doing it, but not as bad, but it progressively got back to where it was again. Just had the tranny flushed and filter changed, but it has made no difference as far as I can tell. The guy who did the tranny flush looked at the fluid and didn't see anything in it showing any catastrophic problems but obviously I need to get the problem fixed, because I'm figuring (I'm no car guy if you haven't figured it out) that its not pumping my tranny fluid right or something and eventually I'm going to have a really really expensive problem. I've noticed other guys on the forums have had their computer's read, I haven't had this done, I have had a engine light on, but the last time I checked it was for a damn gas cap sensor (changed gas cap, still would come on), I guess I should have it checked again.
Any input would be appreciated guys, thanks.
distance is more than likely the thermostatic viscous clutched fan. It will
turn faster initially (when cold)and make more noise, until the viscous fluid decouples
the fan from the fan pulley and the fan starts to freewheel.
The only way you can tell if it's an actual transmission problem is watching
the RPM at the shift points (1->2) and (2->3) on the tach.
If the shift points (set by the PCM) appear to be within a normal range,
then more than likely the transmission is shifting gears. If the RPMs
shoot way up in 1st gear or 2nd gear, then you would have something
to be concerned about.
If that happens you would get hard shifts which are very noticible.
In those cases, it's either the TSS (tranmission speed sensor) or
possibly the TPS (throttle position sensor).
By "shift's into higher gears too soon"..I would presume that the PCM
electronic shifts are taking place, rather than higher pressure induced
"hard shifts" done at higher rpms.
There is a TPS throttle position sensor located on the LEFT (driver's)side of the throttle body.
It connects to the throttle shaft (butterfly valves) and feeds back
information to the PCM on what the throttle is doing at the time.
The second sensor associated with shifting gears, is the Governor pressor
sensor located on the transmission itself. This sensor tells the PCM (computer)
what the fluid pressure is in the valve body (the part of the transmission that
has the fluid activated shift valves to operate the clutches and bands for
the dual planetary gear set and the separate overdrive unit.
The third sensor is the TSS, which tells the PCM the rpm of the o/p shaft of
the transmission itself.
The shift program is learned by the PCM from your driving habits and feedback
from these sensors..which need to be checked out first before considering
an expensive transmission rebuild.
The "chatter" you are referring to..could be the engine "shuddering" because
of the higher gear loading on the engine is too much for the rpm and torque
of the engine at the time....or an actual internal clutch inside the Dodge
transmission chattering because it is slipping on it's friction plates..or
low fluid pressure being delivered by the transmission fluid pump.
There are test ports for determining transmission fluid pressure that a transmission shop can do (with the vehicle running on a hoist) to see
if it's fluid pressure, or worn clutches...or even a bad sensor.
Generally speaking, the transmission should shift from 1st gear to second
gear electronically around 2200 rpm..if everything, including the sensors
mentioned are working correctly.
Shifting from 2nd to 3rd gear is about the same or slightly lower rpm
(1800 to 2000 rpm)
Shifting from 3rd gear to the O/D (4th gear) is around 1800 and then once
in O/D,the engine rpm drops down to about 1500..if you are under 50mph.
The rpm will increase with speed.
I suppose I am not good at explaining. But here today it did it once again. I will try and explain todays actions. It is cludy and 40 degrees today. I left for lunch and got onto the highway and it accelerated to 45 MPH at 3700 rpm. When I released the gas pedal it downshifted and felt like "rear end" locked up. Once again as previously noted it might not have locked the rearend up but thats how it feels. Almost like a chevy drive shaftclanks when u-joints going out. That abript kind of feel. So I gave it the gas again so to not get run over from behind and the RPMs climbed up once again and would only go about 50 mph. It bucked and bronced on me and then the engine light came on. I took it by the Ford house, where I bought it used and the mechanic ran a generic test on it and it showed that the MAF/MAP sensor was faulty. He suggested I go by the Dodge house to have them run a diagnostic test on it. They quoted me(Dodge) 130.00 to test the problem. I did NOT get it done as for it is too close to the holidays and well 130.00 is alot. I stopped by the local Auto Parts store and they pulled a TPS sensor code. I went ahead and bought one since its only 20.00. Have yet to install it.When I got BACK in the truck and headed back to work I noticed the engine light was OFF and then the cruise button stopped working. This also happened last year around the wreck. SO in short I think it may have something to do with the transmission ie the case aluminum may be so cold that something is sticking in it until it reaches a warmer temp?? That is just a educated guess on my end. I DO like the info you gave me and I am sorry I did not explain well enough the last go round. See what this info throws your way.
3700 rpm is definitely too high for 45mph. It appears that the PCM is no
longer involved with shifting the gear ranges, and it's the hydraulic fluid pump
pressure building up, operating the shift valves in the transmission's
control valve body.
The rear end feeling like it is locking up is another indication of ABRUPT SHIFTING taking place..in this case, it could be down to 1st gear ... that is very hard on the transmission components!
The Ford house diagnostic is a red herring. The MAF/MAP sensor is used to
adjust the fuel/air ratio by the PCM and nothing to do with your transmission
erratic/abrupt shifting problem.
The Auto Parts pulling a TPS sensor code, MAY have something to do with it,
but I had a similar case not too long ago..hard shifts and it turned out
to be the TSS Transmission output shaft speed sensor ). It had a low o/p and
the PCM could not read it, so it decided not to bother shifting for me and
all the shifts were HARD shifts at high rpms where the Tach just climbed way
up there... before it finally shifted.
I bought a new TPS sensor, also thinking it was the cause of the problem. Unfortunately the on-line auto parts place sent me a BAD replacement sensor..so I had to put the original back on and tested it.
BTW you can test the TPS sensor still on the vehicle with a Digital voltmeter back probe the 3 wires on the sensor, ignition on but not started, and move the throttle by hand. A good TPS sensor will read 0.5v to +4.5v.... as these are 5 volt sensors.
In my case there was NOTHING WRONG with my OEM TPS sensor and it
is still on my truck shifting properly...my problem turned out to be the TSS
(located on the transmission itself) and eventually the sensor " finally died"
and I pulled a P-0720 code (Low output speed sensor at RPM above 15mph)
"Output shaft speed DETECTED is LESS THAN 60MPH with VEHICLE SPEED
MORE THAN 15MPH."
On the electronically shifted Dodge transmissions, the PCM does the
shifting at the correct "learned" rpm detected by your driving habits.
it uses the input from ALL these following sensors, to calculate and determine
the proper gear shift points:
1. gas pedal-throttle valve position (TPS)
2. TSS ( Transmission o/p shaft speed sensor) tells the PCM what gear the transmission is SUPPOSED TO BE IN ALREADY when in Drive)
3. VSS (vehicle speed sensor..located in the rear differential housing) the pulses
from this one are used to a)calculate your speed on the speedometer,
and b)tell the ABS controller (controller anti-lock rear wheel brakes or all wheel
antilock brakes) what is happening with the rpm on the rear differential gears
4. Transmission fluid pressure governor sensor (this sensor feeds back information to the PCM of what the instantaneous internal control shift valve
body's fluid pressure is..to determine the correct shift points as well.
5. Transmission temperature sensor (tells the PCM when the transmission is
warm enough to go into 4th gear (Overdrive) or when the transmission is
overheating..sets the Trans Temp indicator on the dash.
So as you can see there are several electronic sensors involved with shifting
the gears electronically/automatically for you on the Dodge 44RE transmission.
BTW (44 RE) 4= (4 WHEEL), 4= (transmission torque handling capability)
R=(rear wheel drive) E = (electronically shifted..by the PCM)
Not having a handheld OBDII code reader, you are at the mercy of the
"stealerships" to plug in and read off the code(s) for you... at $130 a pop!
If you want to keep the diagnostic costs down, you need the basic owner's
tools in your tool kit:
1. A Haynes or Chilton manual for your truck year ($30)
2. A cheap DVM (digital voltmeter) around $15-$25
3. A handheld OBD (on board diagnostics) code reader that will scan the
PCM and give you the P-codes (problem codes) when you plug it into
the diagnostic connector located under the steering column.
These are very easy to use, come with a manual explaining the codes
and cost under $60 now.
So for the price of that $130 dealer scan..you can equip yourself with some
very capable tools of your own..and learn how to diagnose your truck's
problems as time goes on.
AND..
"happened around the time of the wreck"
Do you mean this truck was involved in a serious accident last year?
Please provide more details on that.
park? When you move it into D..does it drop in rpm first and then stall..or
stall immediately as you move the gear shift? Have you tried moving it from
park to neutral..what does it do in neutral?
There are many reasons for it to stall..something in the transmission is telling
the PCM to operated the ASD (Automatic Shutdown Relay) or the extra
load on the engine (in the transmission may be causing it to stall
because the gear selection isn't right. )
Are there any check engine codes coming on when it happens?
I'll be calling a few transmission people and see what they have to say.
Using that convention, does that mean that the transmission DOES NOT SLIP
on right turns or when travelling straight?
It doesn't make a lot of sense, since the engine is driving the torque convertor
inside the transmission wheter you go straight or make turns.
On a turn the power steering pump works harder to operate the steering box
and the steering linkage to turn the wheels, but that shouldn't really have
any effect on transmission operation...unless the g-forces in a left turn act on the fluid levels inside the valve body in the transmission in one direction and not the other..