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Toyota Camry Transmission Questions (MY Prior to 2007)

24

Comments

  • sean11sean11 Member Posts: 2
    96 Toyota Camry, 4 cylinder, AT, 140K miles

    Dumb question: I see 2 drain plugs for the transmission and differential, but no filler plug. Where's the filler plug and is there a second filler plug for the differential ?

    Thanks
  • haefrhaefr Member Posts: 600
    "I see 2 drain plugs for the transmission and differential, but no filler plug. Where's the filler plug and is there a second filler plug for the differential ?"

    You fill through the transmission dipstick tube. You'll need a funnel small enough to fit into the tube, or use a plastic tube extension that will. The differential will be filled as you fill the transmission. The only reason for the separate drain plug on the differential was to assure full drainage of that component. Check your owner's manual - if it states Toyota T-IV ATF, DON'T substitute Dexron III ATF. When you drain, you'll end up with nearly half the fluid retained in the torque converter. Refill, button everything up and take the car out for ~6 miles to fully warm and mix the fluid, then drain and refill again. Do one more ride and repeat another drain and refill. At that point you'll effectively only have about 12% of the old fluid left in. If the old fluid smelled burnt, though, better do a fourth drive, drain, and refill.

    (Your question wasn't dumb.)
  • 210delray210delray Member Posts: 4,721
    The differential will be filled as you fill the transmission.

    I'm not sure if this is true on the Camry 4-cylinder. I seem to remember a couple of horror stories about people thinking the differential was filled, but in fact it was empty. You might want to ask on the Maintenance Board, "Got a quick technical question?"

    http://townhall-talk.edmunds.com/direct/view/.ef2398d/1858

    The transmission fluid specified is Dexron III for the '96 (I had a '97, and it used Dexron III).
  • sean11sean11 Member Posts: 2
    Thanks for the info. I think I've located a fill plug for the differential on the back of the diff. near the firewall.
  • haefrhaefr Member Posts: 600
    Thanks for the update.
  • pvdhampvdham Member Posts: 2
    I have 2000-camry automatic transmission with 65k miles. I did a stupid thing... While driving 20mph(and talking with my wife), I shifted the gear from drive to reverse! The car stalled and stopped. I thought its done... I got the car to park and started it and drove it off. Though nothing looks to be broken or sounds weird, what can i suspect to have happend or got affected? Transmission? Gear box? Anything that i can get checked so that the car doesn't die midway... Thanks a lot in advance.
  • icehengeicehenge Member Posts: 9
    Hi,
    Just bought a 1998 Camry and I'm wanting to change the transmission fluid. I picked up some AT fluid, and the transmission pan gasket and filter from pep boys last evening.

    My dilemma is that I want to change the fluid but I know draining the fluid won't complete empty out to old fluid. I figured i'd just drain and refill through the drain plug on the AT the first go around.
    Then drive for a few days then again drain and remove the second time remove the pan and replace the filter and refill again with fresh fluid.

    Anything wrong with this approach?
    The Camry has 106k miles on it and the fluid looks pretty old.
  • bildowbildow Member Posts: 100
    I saw your message your idea is fine I would pull the pan first and you have a mesh screen to clean then after putting back on the pan put in the required oil i think it's about 3 quarts you can ask the dealer about that then drive it a few miles and drain from the drain plug in the transmission pan I would probably drain it about 3-4 times to really clean out the oil. trans at least 1-2 times a year keeping the oil in great shape. If your car is 4 cylinder you also have to drain the separate differential and it has to be filled seperatly by pumping in the ATF using a bottle and pump it does NOT FILL FROM THE MAIN TRANSMISSION. IF YOU DONT FILL IT SEPARATELY YOU WILL RUIN THE TRANSMISSION :shades:
  • loucapriloucapri Member Posts: 214
    I have a 97 and I took it to the dealer and had them power flush the transmission fluid for about $150.00 @ 100K miles. Now my car has 118K and the fluid still pink.
    I understand your apporach but just kind of time consuming and hate to say that, the fluild will still be brown.

    I used to try to save money by doing such job myself (including changing the oil) but as I getting older and see the do-it-yourself result vs. the dealer's work, I just don't see the value. I guess my time worth more than the money I save :)
  • smittycsmittyc Member Posts: 2
    You can actually change virtually all the fluid in the system using the following method. We have 5 Toyota's in the family, and I have done this to them all at least once.
    It takes about an hour. Use whatever fluid is recommended on the dipstick, or in the manual. Our Camry's and Corolla's take Dexron, but the Celica takes Toyota Type IV fluid, available only from Toyota, at about $3.50/qt. Use what's recommended, or you'll be sorry. It's still less expensive than having it done.
    1. Drop the pan, drain the fluid, replace the filter, and reinstall the pan as you usually do.
    2. Add 3 quarts of fluid.
    3. Remove the fluid return line at the transmission (usually the upper of the two lines), and place it into a one-gallon milk jug or similar semi-transparent container. You may want to place the container in a box with rags around it so that it doesn't spill.
    4. Start the engine, and let about a quart or so of fluid get pumped into the milk jug (about 10-15 seconds).
    5. Stop the engine, and add a quart of fluid to the transmission.
    6. Repeat steps 4 and 5 until you get new fluid out of the drain line.
    You'll use about 8-10 quarts of fluid total, including the 3 you put in at the beginning, so you may need more than one milk jug.
    7. Reinstall the drain line to the transmission, start the engine, and check for leaks.
    8. With your foot on the brake, put the transmission in each gear, then into Park.
    9.Let the car down and check the fluid level on the dipstick. Add fluid if needed to bring it up to the proper level.
    10. Take it out for a test drive, and check the fluid level again.
  • skyflyskyfly Member Posts: 3
    I have a '95 Camry with approx. 160,000 miles on it. Currently the transaxle seal is slowly leaking transmission fluid, although I keep an eye on it so it doesn't get low. The dealer quoted me $135 to fix it, but I tend to think dealers charge a little more than someone else who can do the same thing. Also, It has been a little more than 60,000 miles since I had the timing belt changed, and an independent shop quoted me $125 (after a $50 dollar discount) to change it. Are these good prices or should I shop around? Is there a specific type of part that will last longer or are they all pretty much the same.
  • lmacmillmacmil Member Posts: 1,758
    THe leak repair seems reasonable and the timing belt change is as low as I've ever seen. My local dealer charges $260 for a 4 cyl and about $100 more for a V6 timing belt change. My only advice if you are going to an independant shop is get some references if you haven't used them.
  • icehengeicehenge Member Posts: 9
    Hello,
    Out of curiosity I have a question that has me scratching my head.

    The 98 Camry owners manual makes no mention of checking the automatic transmission fluid level. Why would that be?

    I assume the instructions in the Haynes repair guide is correct. Check after vehicle has been drive at least 10 miles, place transmission selector in each gear once, then check fluid level with transmission in park, engine running.

    Why would Toyota feel it necessary to leave this out of the owners manual?

    Alex
  • 210delray210delray Member Posts: 4,721
    That is correct (Haynes manual).

    I didn't realize it wasn't in the owner's manual. I guess not many people bother to check it themselves these days, preferring to leave the job to the dealer or quickie-lubes of the world.
  • redrikkaredrikka Member Posts: 2
    My aunt took her Camry to Firestone where she has a credit line and they told her that she needs a whole list of maintenece perfomed for the 60K service. The technician wrote "trans fluid burnt" on the vehicle inspection. When she called to ask about it they said "it may be discolored, if it is burnt you need to take it to a Transmission Repair shop." They wanted her to bring it in again for service on the trans. after just having it for an oil change. When does the trans. need to be serviced? Why would he say to bring it in if supposedly the trans. fl. is burnt? They had the car only hours prior. I think they are trying to get her to spend a bunch of money since they know she knows nothing aout the car and they are playing on her emotions. Please help, this could cost her a bunch of money that she can't afford. Thank you!
  • 210delray210delray Member Posts: 4,721
    I'd avoid Firestone like the plague. Just follow my advice in post #674 and get a second opinion from a reputable shop. Your aunt probably needs to only have the transmission fluid drained and refilled. Toyota doesn't list trans. fluid change intervals for normal service.

    Don't let any repair shop sell her on a "flush" -- it is expensive and unnecessary.
  • marc781marc781 Member Posts: 25
    No i dont think you are overdoing it. However , you may be using the wrong transmission fluid. My 2002 Camry V6 calls for Toyota T IV fluid, only, as your parts guy said. If you can post a copy of that TSB i would like to see it.
    But Toyota says to use no other kind of ATF other than T IV because it can cause poor shifting. You have got me wondering alright lol
  • redrikkaredrikka Member Posts: 2
    Thank you so much for your reply! I intend to find another shop. No wonder they pass out a credit line to anyone who applies for it! Never again! Thank you! :)
  • icehengeicehenge Member Posts: 9
    Hi,
    I think you've got the best suggestion already. Take the vehicle to get the transmission inspected by another party.

    You can check the fluid yourself though as its rather simple. The fluid is red when its new and discolors with ages and abuse. Also the smell of the fluid will change.

    Here are some links which might help on how to check
    the fluid level.

    http://www.samarins.com/check/transmission.html

    How to check automatic transmission fluid:
    http://www.samarins.com/maintenance/simple.html
  • marc781marc781 Member Posts: 25
    You can smell the fluid yourself. Compare it to new fluid for smell. If it is burnt anyone with a nose can tell. If the trans works ok i would just get by with a fluid change, but i would do it right away. And if it were burnt badly enough to affect operation the driver would probably feel it by now.

    It's a good idea to change the fluid every 30,000 miles to keep it in good shape. You can change the fluid yourself, on the Camry it's easier than most vehicles because it has a trans drain plug, which alot of cars don't.

    If there is a burned smell just change the fluid and then drive it a few hundred miles. Change it again, drive it again, once or twice more. And that will give your transmission a good shot at further life if it is still working ok. Changing the fluid will take about a case worth, 12 qts and this will cost about $20 -25 if it uses Dexron. (Check owners manual on what fluid to use, this is important!)
  • tywitywi Member Posts: 10
    RE: 2002 CAMRY LE 4CYL-at 35000 miles i had a transmission flush at the toyota dealer.i am coming up to 60000 miles should i change the fluid by droping the pan and also changing the filter if there is one.i also changed the coolant at 30000miles by draining the radiator and adding new coolant and water.should i do more more the coolant change this time.
  • 210delray210delray Member Posts: 4,721
    If it's only been 25,000 miles since the tranny was flushed, you don't need to do it again so soon.

    Next time though, refuse a flush. Just drain and refill -- there is a drain bolt on the underside of the transmission pan. Just under 4 quarts will come out -- replace with the same amount of fluid -- Toyota T-IV ATF. True, with a drain and refill, you won't get all of the old fluid out, but that's ok.

    If you changed the coolant at 30K miles (and refilled with the original Toyota super long life coolant), you're supposed to be good for 100K miles. Some say, however, not to wait that long.

    When you do change it again, it IS better to flush with water so you get all of the old coolant/water mixture out of both the radiator and engine block.
  • afm127afm127 Member Posts: 1
    i have just recently changed the transmission pan and fluid in my 1995 toyota camry LE.... i drained the transmission and the transaxle transfer case... Not realizing that i had to replace the fluid in the bottom of the transmission for the transfer case, i just put fluid into the transmission through the dopstick tube... now after driving the car back an forth from a friends house down the street from me about 3 times i cant change gears..... i put the car into drive and my speedometer will go up as if i am driving but i wont move... i have been told by a friend that this might be a diagnostic problem where the car knew that there was no fluid in the transfer case and disabled my transmission.... what is the proper way of resolving this problem?
  • carpluscarplus Member Posts: 1
    Hi Everybody..

    I have a 2003 Camry SE 4Cyl Auto that has a peculiar problem. It seems as if whenever the temperature rises, the car has a tendency to not shift out of park at all. The pedal can go all the way to the floor, handbrake down, ect... but the darned thing won't shift out of park. Now this only seems to happen during warmer temperatures and only just recently seemed to happen. Anyone have any ideas or similar problems?

    TIA
  • jddepuejddepue Member Posts: 2
    Can anyone suggest what might cause my 91 4 cyl to jump out of 5th gear when accelerating or pulling a hill?

    Thanks
    Dave
  • ray_h1ray_h1 Member Posts: 1,134
    I had an '82 Peugeot that would pop out of 2nd gear unless I kept my hand on the shifter. Turned out to be nothing more involved than a simple linkage adjustment the dealer took care of in five minutes. But, not all gear jumping's that simple - best to have a transmission specialist look at your car. A misadjustment the wrong way or amount can also accelerate internal transmission wear.
  • bildowbildow Member Posts: 100
    I put tranny coolers on all my cars including the 2006 camry and 2000 Lexus I live in southern California and I am a salesman and I drive in bumper to bumper all the time I also use synthetic trans fluid in both cars using Amsoil due to the type of transmission fluid that toyota/lexus uses. They use a type 4 trans fluid so Amsoil says their oil in compatible so far no problems. My toyota cressida using a transmission like the lexus and toyota truck ran 385,000 miles on the same trans using mobil one tranny fluid due to the older cars could run the dexron 3 from 2002 the camry runs type 4 fluid you can also buy it from the dealer and change it your self just use the drain plug in the tranny and I change all my tranny fluids at 20,000 and synthetic fluid is supposed to run 50-100,000 miles I also change my power steering fluid with synthetic tranny fluid at 20,000 miles for the engine I use mobil one 5-30 getting 200,000 to 400,000 miles on the engine use synthetic oil in cold weather it will go down below 0 and still work.
  • pb1millpb1mill Member Posts: 1
    I own a 1994 4 cyl LE. Recently, the transmission has been hesitant to shift into high gear until the car has been running for a while, espescially when it is cold. I sometimes have to drive 8-10 miles before it shifts into high gear. The trans fluid level is good. What could be the problem?
  • ray_h1ray_h1 Member Posts: 1,134
    If you're lucky, just a gucked-up valve body. How long has the current fluid been in service?
  • mamapmamap Member Posts: 2
    Can anyone tell me what's going on here?

    First: The speedometer/odometer cut out and works only sporadically
    Second: The car began to stall at stops RPMs drop sometimes while still stopping, other times once stopped or in park
    Then: Had my husband change spark plugs and problem stopped for a few days then came back and..
    Finally: Transmission does not always shift while accelerating. For insatance-was doing 15mph at over 3kRPMs.

    All of these things happened within about a week of each other. I had my transmission fluid replaced and a leak repaired at the end of November.

    Thanks for your help!
  • vicuvicu Member Posts: 1
    When the car is cold, I can't get it into gear until the engine warms. Even when I warm it up for about 15 minutes, when I put it into drive, there is another 1-2 minute wait until it engages. Once engaged, the gears run smoothly, and for the rest of the day, the car is fine, even after repeated stops to various stores. I was thinking about changing the oil and filter, but the tranny has not been serviced for a long time, and I'm afraid I could make it worse.
  • 210delray210delray Member Posts: 4,721
    Sounds like you need to get the transmission looked at pronto, by a reputable shop. Get recommendations from friends, relatives or co-workers. You don't have to go to a Toyota dealer.

    If you know how to check the tranny fluid level, you may at least want to do this first.
  • luigi2025luigi2025 Member Posts: 1
    I've had my 2000camry LE, V6 since new. I only have 50,000 miles on it. Two months ago when driving in rush hour, stop and go, freeway traffic the car started kicking whenever I took my foot off the gas. Happened most often if I was accelerating and then had to lift my foot off gas to put on break. I'd get a slight bucking, and thump-thud noise. It got progressively worse and I took to the dealer. They replaced the bone joint and motor mount. I picked it up and drove it and no change to the problem. I had to drive with the technician because they were testing it in straight freeway driving and the problem was not occuring. I had them simulate stop and go traffic and then they felt it. Said it needed a new transmission. They put in a whole new transmission--no change to the problem. I took it back and they said it was a problem with the throttle cable. Tightened that. I drove it today and now it's worse. Not only happens when I take my foot off gas but now sometimes happens when it's shifting gears. It's much worse when the car is driving between 40 and 50mph.
    I took it back and they say there is nothing wrong with it. HELP!
    (My husband said he thought it was the U joints but the Toyota people say this car doesn't have U joints.)
    Thanks for any help you can give. I'm frustrated and it's an uncomfortable ride but I can't afford a new car right now.
  • agellius3agellius3 Member Posts: 4
    I'm no expert, but just a shot in the dark: Years ago I had a problem that sounds similar to yours, with bucking and hesitation. It turned out to be a dirty fuel filter. Hard to believe they would not have thought of that, however it's a cheap repair so it might not hurt to try it.
  • jophil28jophil28 Member Posts: 1
    I am planning to attempt to change the transmission oil. I have an engineering background and a garage full of tools. SO what type of fluid do I buy for that model/ vintage. What else do I need to do or replace.
    This is our 'standby vehicle' and the fluid is VERY brown and the vehicle has started jumping out of gearoccasionally..The transmission has also been OVER filled.
    Any assistance greatly appreciated.-
    Thanks , John.
  • sean300sean300 Member Posts: 41
    I know that this is the Camry transmission questions section but no one seems to be answering my question in the "Transmission Trauma" section. I have a '98 Lexus ES300 with 152k miles. About two weeks ago when the engine wasn't quite warm I got a hard shift and a thump when shifting from park to reverse. When the car warms up it disappears and shifts fine. Anyone experience this. The last time that I changed the tranny oil was 137k miles. Your advice is greatly appreciated.
  • wwestwwest Member Posts: 10,706
    In the olden days, days gone by, my first thought would have been worn u-jounts, nowadays excessively worn CV joints would be the most likely cause.

    Next time when the car is cold try turning in a tight, the tightest, circle while driving slowly forward and see what kind of sounds you get from the CV joints.
  • sean300sean300 Member Posts: 41
    Thanks for the advice. I'll give it a try. I went to my mechanic who said that the tranny fluid was fine. He said that he has a tranny guy who could take a look but offhand his thoughts were something internal like a shift solenoid. I'm not sure about that because the other gears shift fine.
  • sean300sean300 Member Posts: 41
    wwest, I did listen to cv joints - no sounds from them and drive boots are intact. So I took the car back to my mechanic who took it to his transmission guy to check it out. My guy returned back to his shop with my car and he said the tranny guy said that there were no codes in the transmission. The tranny guy concluded that all of the engine mounts needed to be replaced; he felt that the clunk was due to this. My guy said that the rear mount was the worse - supposedly shot. He quoted me at $700 parts & labor. I feel that the mounts are not that bad. Has anyone had this issue? Will it cause real problems if I elect not to replace the mounts. A friend of mine has a "95 Camry V6 coupe with almost 200K miles on it and he said that he never changed the mounts and had no problems - his car is older than mine's. What do you folks think?
  • 210delray210delray Member Posts: 4,721
    Why do you think your engine mounts are not that bad?

    Maybe you can get a second opinion from another shop -- your original guy should have been able to spot the bad mounts before the car was sent to the tranny guy.

    I don't think it's too wise to have the engine/tranny flopping around if the mounts are indeed shot. But maybe you could replace just the rear one first if you want to minimize costs for now.
  • sean300sean300 Member Posts: 41
    I don't think that the mounts are bad because it does not feel that bad. I'm not a mechanic but it just doesn't feel like my engine and tranny are "flopping" around. I looked at the torch strut (passenger side by coolant reservoir) and it seems tight and there is no deterioration of the rubber. Also, my guy has looked at the car extensively prior to this and he never mentioned bad mounts - I take it to him exclusively. He only said that the rear mount was really shot. Like you said, I think that he would have caught this a long time ago. But, I also agree with you about just replacing the rear mount for now. My mechanic does not have a problem with installing parts that I buy and supply to him. I searched eBay and the rear mount is only $49 new. Labor should not be that much since I'm only replacing one mount. Thanks for the advice.
  • bkamalibkamali Member Posts: 4
    Hi All,
    I have a Toyota Camry V6-XLE, year 1997 and about 175000Km on that.
    A couple days ago I noticed that when I go from Neutral to Direct, there is a sudden movement on the motor. So far it never happened when I start the motor and it is cold; but it happens when the motor and transmission are warm.
    It happens occasionally. Sometimes everything is good but sometimes it happens. The transmission oil has been changed (flushed) about one year ago.
    I appreciate any suggestions about the probable cause.
  • 210delray210delray Member Posts: 4,721
    You're quite welcome. Sounds like you have a good solution for now; also if you have a trustworthy mechanic, that's great.
  • 210delray210delray Member Posts: 4,721
    If the engine is actually moving with respect to the rest of the car, it could be the engine mounts -- see the past few posts.
  • sean300sean300 Member Posts: 41
    I had the same problem with my '98 Lexus ES300. The front engine mount was bad (attached to the frame of the car and the engine bracket by the alternator and the belts). The mount is commonly called a torque strut or referred to as a "dog bone" (shaped like one). It was replaced and all other mounts were checked and found to be good. I still have some movement but I am told that it is minimal, the mechanic said that the engine has to have a little give because the mounts are made of rubber. I have replaced this mount on my previous cars which were two camries ( '92 4 cyl. and '95 v6). Do you also hear a clunking sound accompanied by a hard shift or jerk when putting the car in gear? This would occur with my car when moving the gear selector from park to reverse and a little in drive.
  • sean300sean300 Member Posts: 41
    210delray, see post #104. It was not the rear but the torque strut. You will see the rest in the message.
  • sean300sean300 Member Posts: 41
    Hi. I posted on es300/330 forum, but I wanted to try this one too, since Lexus is made by Toyota (Camry). I am still having issues with tranny/engine mounts. Replaced the front (torque) strut but advised to change the other three mounts too. What may or will happen if the mounts are not replaced? I am assuming that these are original mounts - have 150K miles on the car. Others have said that they have more miles and have no issues.
  • bkamalibkamali Member Posts: 4
    Hi,
    Thanks for advice.
    I noticed something else, which is the shifting happens in 3000 RPM, normally it was less than 2000RPM.
    Do these problems relate? (probably yes) What is your opinion?
    Regards
  • sean300sean300 Member Posts: 41
    I am not sure but my es300 shifts in second gear around 4000 rpm' s. The mechanic that changed the dog bone mount said that it is shifting a little late but may be because of the mileage and the age of the car. He also said that the important thing is that the tranny is shifting fine. A guy on the es300/330 forum (Larry1) said that his 1992 es300 was operating fine when traded in at 255K on the clock with the original engine and tranny. So, in short, I don't think that you or I will have any major problems with our cars. I mean, Camrys and Es300's are similar and both made by Toyota. In answer to your original question, I really do not know if the two issues coincide.
  • wwestwwest Member Posts: 10,706
    [quote name='kolkh' post='127828' date='Sunday, Sep 2, 2007 @ 06:24 PM']DISCLAIMER:
    Previous post is not a simple reply – this is actually 11-th edition of “Wwest Mythology”. Previous 10 editions have been discussed and bitten to death in approximately ~1000 posts in a number of forums/sites. I have read some of those. What is the result? See here:

    [url=http://www.siennaclub.org/forum/index.php?showtopic=6921&hl=]http://www.sie- nnaclub.org/forum/index.php?...ic=6921&hl=[/url]

    As if previous discussions do not exist, wwest posts the same stuff again and again and again…
    Like a Big Propaganda Machine, wwest is in a win-win situation: if you start infinite discussions and win – it does not mater, next time he will post exactly the same stuff. If you ignore him – he will flood forums and poor readers would have to deal with it anyway.

    END OF DISCLAIMER[/quote]

    Okay, "teacher" will take a different tact, tactic.

    Do you know how many things in a car simply waste energy....???

    A) Power stearing hydraulic pump when there is no "stearing" to be done. What, 98% of the time?

    And yes, I do know that PS pressure helps "hold" the stearing in a "set" position, but just how much energy does that require in comparison to the HUGE losses?

    The PS must have the pumping capacity/volume/displacement to help, SERIOUSLY help, turn the wheels at or near a dead stop(parallel parking...), all the while with the engine turning only at idle, of maybe slightly above.

    So, 2200 RPM and driving straight down the highway at 65MPH guess how much pressurized PS fluid is simply being bypassed back into the sump.

    Is it any wonder that many cars are converting to electric power stearing, even at the risk of having the solid state electronics overheat and therefore automatically going into a sub-standard power assist mode?

    B] Gear-type engine lubricating pump. Again, pumping volume/capacity/displacement must accomodate full pressure and flow even with the engine at idle. So as engine RPM rises the EXTRA pumping capacity must be bypassed back into the sump.

    Either BMW or MB, don't remember which, has already gone to a variable displacement engine lubricating oil pump in oder to reduce these losses and thereby reduce the engine heat load and also increase FE.

    C) A/C compressor. Here again, the compressor pumping capacity must be such that it can provide FULL cooling capability at engine idle on a BRIGHT and SUNNY 100F (or above) day. In this case the A/C clutch along with a reasonably sized liquid refrigerant storage reservoir has been used for "eons" to ammiliate the effects of continuous engine loading by the A/C compressor.

    So why do you suppose so many new vehicles are coming out equipped with the new variable capacity "swash plate" type A/C compressor, and the compressor clutch?

    Because it is better design practice, overall, to have a continous ~2HP load on the engine rather than an intermittent load of ~7HP.

    [b]Getting the picture..?[/b]

    D) And just what is the deal with the torque converter (hydraulic TURBINE pump, slush pump, etc.), just how lossy is that sucker?

    The slush pump, torque converter, is really required ONLY to act as an automatic clutch. At low engine speeds, idle, the losses are so high that virtually no torque is coupled to the transaxle input shaft. NONE would be ideal, but nowadays you need a clutch pedal for that. The nice thing about the torque converter is that it also acts as a reduction gear ratio at low torque loading. But, that's where the torque converter lockup clutch comes into play. In OD it is highly desirous to have the engine operate at the lowest speed at which it can produce "just" enough torque for the current load factor...roadspeed. So at low engine RPMs the HIGH LOSS torque converter is bypassed by the lockup clutch.

    E) This one is slightly off point but I bring it because if I don't someone else will.

    The engine coolant water pump.

    Almost all engine coolant water pumps are of the centrifical, turbine, type and thereby self limiting insofar as pumping volume is concerned. Obviously there is some "needless" loss involved here otherwise the water hoses would not "swell", balloon, as engine speed rises beyond the point wherein the thermostat will accomodate the pump volume. Other than the current crop of hybrids, all equipped, to my knowledge, with electric water pumps, other manufacturers have already converted to electric pumps, if not altogether then at least apartially so, for the cabin heater.

    [b]Get the picture..?

    No...?[/b]

    F) And finally....

    The gear type ATF pump.

    Like everything else above the most critical situation insofar as determining base pump volume occurs with the engine at idle.

    Hmmmm..

    Let's think this over a bit.

    Just what "work" does the ATF pump have to do with the engine at idle?

    Shifting from park or neutral to drive or reverse is clearly not critical insofar as pumping volume is concerned...

    Upshifting once underway always involves engine RPM well above idle....

    Aha, DOWNSHIFTING....

    So, when does an automatic downshift with the engine at idle or nearly at idle.

    Not for passing, kickdown, certainly...

    But then how about just before coming to a full stop...?

    Or during coastdown periods with the throttle fully closed...?

    In both of these latter instances if the transaxle is to downshift lots of ATF pressure/flow will be required to ascertain the downshift clutches are quickly and firmly seated. Otherwise, with low or marginal ATF pressure these clutches would undoubtedly incur some serious level of slippage and the wear associated thereto.

    So, the engineers say to each other, if we could eliminate just these two instances the ATF pump FIXED capacity could be a LOT lower and that would undoubtedly inprove FE overall while reducing the heat load and clutch wear rate.

    Say, what does a stick shift driver do in these instances. Well as the cars coasts to a stop teh driver would normally disenage the clutch and slip the transmission into 1st.

    Well, we can't disenage the clutch....Can we...??

    Sure can, simply "upshift" the transaxle a few notches, no substantial level of engine compression braking, NO transaxle clutch wear. Who cares if the upshifted clutches don't quickly fully and firmly engage...!

    But what about coastdown periods at 40-30MPH with the engine at idle...?

    Why not upshift then too, who's to notice?

    ________________________________________

    The theory behind the above dissertation arose because I noticed a seeming abiguity between my earlier theory, "protect the drive train using DBW to prevent engine compression braking.'

    Owners have been reporting that while in cruise control the engine/transaxle ECU will actually command a downshift to retard roadspeed going down a hill.

    Me..."What? Downshift a FWD or F/AWD vehicle and actually take advantage of engine compression
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