Transmission fluid change-which method is better?

doitmyself

This question was asked about a year ago, but everyone got off the subject. What are the pros and cons of the two transmission change methods:drop the pan, change filter, change half the fluid versus pumping out 100% of the fluid with no filter change. I have a '99 Ford Escort and the manual just says "service the transmission fluid every 30,000 miles". The Ford dealer wanted $120 dollars for the pump out method.

pjksr

Do you know how Ford claims to be able to pump out 100% of the fluid? Aren't there cavities and crannies and torque converters where fluid can't be reached without disassembly?

I've found transmission shops can service your fluids for about $50.

You can drop the pan and change it yourself for a lot less than $120, too. Even multiple times. Just be sure to spread out a bunch of dropcloth and wear goggles!

Also, there are "oil extractors" out there...I hear they work. Search the net under "oil extractor," or check out the Edmunds forum under "oil changes."

zr2rando

You can get a kit to install a drain plug for the pan so you can empty it before dropping it to change the filter,,,but you have to drop the full pan the first time to install it..oh well, so much for the easy first time huh!!
While under warranty I would do what the book says to do.
After the warranty I would do the 100% fluid flush about every 30k and change the filter after every other flush. Keeping newer fluid in the transmission helps keep seals in good shape and keeps the fluid properties at new fluid levels and avoids any heat related decomposition from being a long term issue. The transmission filters I have seen did not have any blockage issues, the main issue was the fluid condition

alcan

Remove the pan. Replace the filter and reinstall the pan. Add about 4 quarts of fluid. Remove the cooler return line (from upper fitting at rad) at trans and attach a length of hose to direct fluid into a catch pan. Have an assistant start the engine and pour fluid into the trans at the same rate it's being pumped out. When the discharge is clean fluid, shut the engine off, reinstall the cooler line and top of the trans in the usual manner.

kmag

Maybe Ive just been lucky. My 94 escort GT has 115K miles with 1 transmission service at 75K. I had it pumped at the local oil change place. Tranny shifts just as rough as when I bought it at 20K miles

CLick & Clack, the guys on NPR, said that if you have 75-100K, dont open it up, its just as likely to cause problems.

armtdm

Many newer cars have a drain plug for tranny fluid. I have a toyota, Merc, Isuzu that have plugs my GM product does not. So a drain and fill is very easy. On my 92 Toyota I did the first drain and filter change (dropped the pan) at 25,000 miles. I have only drained and filled via the plug every 30,000 since then (have not changed the filter since 25,000) and now have 142,000 on tranny. Granted you only get about half the fluid each time but that is fine. I use synthetic ATF

A "flush" (not a pump out change ) is fine but "no one does it properly" due to cost. After flushing the system the pan should be dropped as the gunk is removed and sits in the pan and can and has caused problems.

Now, if you are simply pumping out the old fluid via the cooler line then that is fine. However, overall I think this is overkill. For the cost of fluid (if you have a plug) drain and fill yourself. Measure the amount taken out as this is much easier then filling up and overfilling as it is a pain to remove the fluid if overfilled. Remember, check when tranny is hot and engine running.

alcan

"A "flush" (not a pump out change ) is fine but "no one does it properly" due to cost."

No one does it properly? Not one? Nobody at all? Anywhere? Ever?

Btw, some newer models of flushing machines attach to the trans at the pump suction port normally occupied by the filter. They make a bit of a mess but they replace all of the fluid. Every drop. How one could attach one of these flushers to the trans without first removing the pan and filter is beyond me.

armtdm

The reason no one does it properly is cost. After flushing the tranny with their solvent they refuse to drop the pan saying it is not necessary due to cost (and they claim the flush got everything out) . It would add more time/labor plus new filter gasket etc. and they already overcharge for the service and the customer does not wan tot pay more as well.

alcan

Who's this "they" you refer to?

8u6hfd

$90 for a drop the pan, change the filter, etc. for our 93 Caravan at a Arlington, VA shop sounds good to me. A drain and refill at the dealership costs almost as much.

For the Caravan, it's cheaper than a new transmission.

rayfbaird

Since in the past they have been a weak component, I drain the fluid, replace the transmission seal and filter every 15K. Since you've gone 30K I would recommend a complete flush in addition to the procedure described above. If I have full synthetic then I go 30,000.

alcan

$90 is reasonable considering that Chrysler vehicles up to 1999 require the usually more expensive ATF+ (Type 7176) fluid. Btw, you should verify the fluid used, as DexronIII/Mercon may cause torque converter clutch shudder and/or deteriorated shift quality.

brucer2

Not all pans are on the bottom. The Nissans (we have/had) were on the top. The Ford I have has it on the side. Neither has a replacable, paper/fiber element filter, but a screen instead. I don't think the screen can be reached in either trans without a fair amount of disassembly (I know the Nissan can't). For transmissions like this, that have neglected fluid, a chemical flush is probably in order. When a flush agent is used the drive wheels should be off the ground, and the transmission shifted through all the gears so all the solvent gets to all the parts of the trans. For DIY types, who don't have a flush machine, try putting 4 - 6 oz of Marvel Mystery Oil in the trans a few days before having a complete fluid exchange done. The MMO has a "gentle", slow acting solvent that will disolve the varnish. I wouldn't do this if only a drain and refill was being done. (I actually did the MMO on a 10 year old Maxima with 40k city miles and the shifting was quicker after a couple of days. Did a full fluid exchange after 3 days. Now with synthetic ATF and an added cooler, the trans doesn't get "mushy" after sitting in bumper-to-bumper traffic, in the middle of summer with the AC on.)

aurora5000

Alcan- I do the same but I am the only one involved. I know what my capacity in tranny is and I do the cooler line deal but do one quart at a time. I have my cooler line into a 1-quart container. When it fills up (usually in 10-15 seconds,) I shut off engine and add 1 quart, then start the process over. I know it it tedious and slow but it works. Also I check each quart coming out in a big white styrophone cup looking for the cherry colored fluid from the first quart put in.
Change at 10K.

alcan

Yep, that'd work. Also gives you a chance to check cooler flow rate. General spec is minimum 1 quart/20 seconds.

spokane

My procedure is similar to yours, Aurora. The flow rate is often too high for me to add new ATF at the same rate it is being discharged.

Alcan, can you please clarify a point regarding torque converter pump-out. Isn't there considerable mixing of the old and new ATF as the new ATF is pumped in because the path through the converter is not one of First-In/First-Out? Isn't it necessary to put some 7 or 8 quarts of new ATF through a 5-quart converter to achieve a reasonable purge percentage of the old ATF? I am not familiar with solvent flushing but, if you are purging cleaning solvent from the converter with new ATF, what is the criteria for being assured you have "gone far enough?" Thanks.

Am I the only one who misses having drain plugs on the torque converter as some had 30 years ago?

aurora5000

No you are not the only one who misses the drain plugs in TCs. Those thrilling days of yester years. I read somewhere in my Aurora 4T80 tranny had a drain plug in it... don't have service man. yet.

I appreciate all who contribute to the board...

What's the story on synthetic fluid and changes?

I usually change trans fluid every 10K.

leadfoot4

I purchased a 2000 Lincoln LS last year, and it doesn't even have a dipstick/fill tube !!

swschrad

there 'ya go, a true lifetime transmission. once the clean is used up, the lifetime is over. curious that they didn't do the same thing with the engine and the gas tank....

burdawg

I miss the dipstick. To refill the trans on my Grand Am:
1. Remove fill plug/vent cap.
2. Refill minus about 1 quart.
3. Jack up car, remove right front wheel so you can see level hole easier.
4. Start engine. Let it run long enough to warm up trans to operating temp. Shift through all ranges to distribute fluid.
5. Remove oil level plug in side of trans. Engine should still be running.
6. Lower jack down so car is relatively level.
7. Add fluid until it comes up to bottom of level plug hole, or till it just runs out (easier unless you like jumping up and down a lot).
8. Replace level hole plug. Don't turn engine off with the plug out unless you want to start again.
9. Jack car back up, put wheel back on.
10. Don't forget to put the fluid fill/vent cap back on.

leadfoot4

The process that's outlined in the Lincoln shop manual for my LS is similar to the "scenario" that you describe.
I had the car in the shop last week for a minor warranty repair, and I was discussing the tranny fluid thing with the service manager. I asked him about doing a change,(they have the flush&fill machine) and he said,"Save your money, bring it in at 30,000 miles". They did, however, put it up on the lift and check the level.
I'm used to doing my own maintenance, which involved changing the fluid and filter annually.

gsleve

if you used a gallon milk jug after washed it out thereby you could multiply the time factor by 4 and it would save you a little more time

lukjack

I just bought a Buick Rendezvous. The maintenance manual does not call for a tranny fluid and filter change until 100,000 miles. I am not sure if I want to wait that long. However, I did get the towing package because it comes with a transmission cooler, as heat is the number #1 killer of transmissions....Any thoughts??

aurora5000

I think I will try that on my wife's car. She has a GM "Turbo 400" Tranny in her car. That's going back a few years....

armtdm

I also have a Buick (Regal) but I believe the schedule is the same. Mine is 50,000 severe service and 100,000 normal. Problem with GM products is that they have no drain plug, have to drop the pan. I am considering pumping it out via dipstick arouond 25000 and doing the drain and fill route.

aurora5000

I changed tranny fluid today with the "gallon at a time method". I used 1 gal. plastic anti-frezze fluid containers and watched as it filled up. It would only fill up 3 and 1/2 quarts at a time and then stop. It took about a minute each time to fill. I did that 3 times and changed out 11 Quarts.
Thanks for the friendly advice, neighbor.

tntitan

I have a 2000 Accord SE and have no idea if I can change my own transmission fluid or not. If someone knows my 4cyl. engine well enough to walk me through a detailed description in idiotproof terms then I am willing to give it a shot. Same thing with my brake fluid. I am approaching 30,000 and don't want to wait on the brakes. The manual says 45,000 the first time and then every 30,000 but I don't see what is different. With ABS it seems wise to do it every 30,000. Help!

The best answer may be to just "pay the man".

adc100

I would consider dropping the pan. For years, I avoided the job and had it done (even though I'm a decant mechanic). I have a set of those "Rhino Ramps" available for usually $29. I would recommend just running it up on the ramps and clean everything off underneath. Make sure that you can get a socket on all of the pan bolts. Once you see there are no interferences, you probably will want to tackle it.

If you take your time and loosen it up such that the oil drains out of one corner its not really messy. When you pull the filter off make sure that the rubber gasket/oring comes off with it. When going back together use a light coat of grease to hold the gasket in place. The filter rests on a shelf attached to the housing. Difficult to screw up.

The only trouble I had was the torque value of pan bolts. The manual indicated 96 in/lbs. The filter box indicated 144 in/lbs max. I went with about 120 in/lbs and had leaks. Went to 150 in/lbs-no problem. Filter/gasket kit was $8 at Advance.

Al

zr2rando

If the filter comes with a cork-burger filter be leary of it, they sometimes are a little bit off-sized, almost like they shrink up when they cool after being stamped out at the factory, and sometimes they start leaking later in life too.
Napa has good filters and good (quality material and THICK) gaskets come with them, but they are more expensive at Napa.
Like ADC100 said, make sure you have pan clearance, I have a 95 s10 Blazer and the back part of the pan is above a frame cross member which had to be removed to get the pan out (it only lacked clearance by about 1/2 inch!!)
Most vehicles do not have that type problem though. Good luck!

adc100

You are exactly right. The interference was in a 92 Corsica, the problem was gettting a socket in there. A 1/4 inch drive solved that problem. Its tight on other GM vehicles also-amazing!!

armtdm

My pan is actually a clear view, nothing in the way. Plus, I have a drain plug so it should not be as messy. I have never put a fitler in so I am leary of the first time syndrome and leaks but I think I will give it a try.

As to the torque, I have basically given up on the OEM recommendations. Especially for valve covers and oil and tranny pans. Valve cover I could almost hand turn when it started to seep so now I re torque via the "seems tight to me method". In my experience it seems better to over tighten (not to strip or break) these bolts. The dealers and mechanics seem to have the opposite belief and I wind up having to tighten them when they begin to seep.

I do have ramps so time to give it a try

armtdm

My mechanic says that for the most part when they replace a tranny filter it is basically clean, especially those with screens rather then true fitlering material.

What has been you experience, how did the filter look when some of you replaced it?

adc100

But not out of control. There is also a magnet epoxied to the inside bottom of the pan it will be very very dirty. My transmission fluid was very/very clean. The car had 127,000 miles and the oil had been changed last at about 60K (Mobil 1 syn) Friend of mine has a Chevy Van and his oil was very dark and the filter very dirty. Helped him change and that gave me the confidence to do mine.

zr2rando

I have a 95 s10 blazer and a 99 s10 p/u, both have the same transmission, filter uses a fuzzy fabric material (dacron I think),not a screen.
99- change all fluid (fluid-exchange at quickie-lube place) at 30k, and pan/filter at 50k, added Lubeguard at 50k change-------------filter material still looked like new (not exactly but very clean for what I expected) at the 50k change.
95- pan and filter at 52k, all fluid at 75k, all fluid at 98k, pan and filter at 125k, added Lubeguard at last pan/filter change.----------------filter material was slightly darker than new material, but still in very good shape.
I did the pan/fluid changes at Cottman's Transmission, price was good ($30 for labor and fluid (not synthetic),, and the 95 has to have that frame member undone (stupid Chevy engineer tricks!!!!),
From what I have seen, the main thing for trannie fluid is to check periodically for color and smell, making sure there is no overheating issues that would be breaking down the additives. If it does not get overheated, the DexronIII actually seems to last pretty good,,,,,LOTS better than the older DexronII ever did.
Both transmissions are shifting as well as when new, (knocking on wood as I type!!!:)

mike1qaz

There is no pan to drop on Honda's auto trans for the I-4 Accords (98-02). Also no filter to replace. Simply drive the car to warm up the transmission and remove the drain plug. Monitor how much fluid is drained and replace that amount of fluid through the transmission dip stick tube. Be sure to use the Honda atf-z1 fluid!!! Your user manual will show you where everything is located and walmart has the metered funnel with hose to make the replacement easy.
The brake fluid replacement is a different story. In another life I used to work summers at my dads service station. Back then we used a power brake bleeder to supply fluid under pressure and cracked the bleeder valve at all 4 wheels. I don't know how they do brake fluid replacement today, but i assume it is similar to this.
30K is premature for both of these fluids to be replaced. However its your car and your money.
Happy driving.

tntitan

I really appreciate your explanation but being a total idiot I still have two questions. Do I use the metered funnel to measure how much fluid I drain? Can you give me a ballpark estimate of how much fluid I should be able to drain (I need to know what size container to have)? This actually sounds like something I can do.

The manual says to change the transmission fluid at 30K. If I have the brake fluid changed at an independent garage will it matter if they use "Honda" brake fluid?

mike1qaz

The amount drained is less than 3qts. The funnel is used with the new fluid only. By the way, my 01 lx accord manual says to change my trans fluid at 60k for severe conditions and every 30k thereafter. 120k for normal conditions.
That's quite a bit different than your 2k model. I changed mine at ~45k. I now have 62k on my 15 month old accord and no problems to report other than the odd rattle here and there on rough roads.

For the trans and power steering it is important to use honda fluids. I'm not sure about the brake fluid.

tntitan

I checked the manual and it does say every 30K for severe conditions for the transmission fluid and every 45K for the brake fluid. I am going to give the transmission fluid a shot myself and wait on the brake fluid until 45K and let an independent garage do it.

Is power steering fluid something I can easily do myself?

It is strange that the change interval changed so dramatically in only one model year. It kind of bothers me with all of the automatic transmission trouble on the Accord thread. Thankfully mine has been fine and I hope changing the fluid is all I need to do to it for about 10 years.

prophet2

Check this one out. My brother-in-law just called me and said that the Acura dealer's service writer claimed that his MDX needs a total transmission flush with the special machine ........... at 7500 (that's tight, SEVEN THOUSAND FIVE HUNDRED) miles! What do you guys think of this?

Now, I'm a believer in preventive maintenance and had the engine, transmission, and cooling systems flushed on my pre-owned 3.5RL, but these services were done at 45K/4 years, not 7.5K/six months!

bburton1

Look at the owner's manual and I really doubt if this is called for. Sounds like to me the dealer is making an assult on your BIL's wallet. I wish someone would try that stunt on me-love to yank their chains. Sadly there are thieves out there-I would not go to these people again. They might do damage to the vehicle in order to generate additional income. Slashing CV boots is high on this list.

Regarding Honda ATF-got a tranny code at around 70K-turns out my fluid was a bit burnt and discolored. Changed the ATF using honda fluid and reset the CEL and no problems 60K later. Would suggest changing ATF every 30 to 35K. I think mine requires about 2.8 quarts. You will need one of those funnel things with a long clear tube attached to pour the ATF into the ATF dip/fill hole. Oh and drive it at least 30 miles to get the ATF good and hot. Be very careful when removing the drain plug-that fluid gets extremely hot and can fry your skin. I wear protective gloves and am very careful-it really squirts out. Changing atf is easier than changing oil.

adc100

Sounds like you didn't finish the job. Check your owners manual for total capacity. You normally have almost half the fluid in the torque converter. If your fluid was burnt it may indicate a problem or at the very least you need to drain and fill with running the vehicle in between to get most of the fluid out. Alternative is to do a flush as has been previously mentioned here.

chikoo

1. drop the pan/ open the drain plug
2. drain the fluid.
3. close the pan / drain plug
4. Start the engine
5. shift through gears
6. drop the pan/ open the drain plug
* I assume most of the fluid from the Torque convertor must have now been pumped into the gear area *

7. drain the fluid.
8. change the filter
9. reseal the pan / drain plug
10. Start the engine
11. add ATF through the ATF dipstick hole

Anything wrong with this method?

alcan

Plenty. The trans pump picks up fluid from the pan then sends it to the hydraulic system (main pressure regulator), which in turn supplies the converter pressure feed. With no fluid in the pan there's nothing for the pump to pump, no hydraulic pressure developed, and nothing forced into the converter to push the old fluid out.
Also, shifting into gear with virtually no fluid pressure will allow clutch/band slippage.

armtdm

Had the filter (metal frame holding a fine mesh/nylon screen), and fluid changed today in my Camry. The last time the filter was changed and pan dropped was at 25,000 when I switched it to synthetic ATF. Changed the fluid every 30,000 via a drain and fill (has a drain plug) since and now at 143,000 decided it was time to drop the pan. 118,000 since last filter change.

So, filter had caught very little contaminants, a few specs of debris here and there but basically clean. Now, the magnets (3 of them in the pan) were all covered with debris, more like thick oil and pan was basically clean. From what I could see into the transmission after removing the filter it looked really clean, no varnish, no build up of any kind, clean metal and whatever else was used. However, based upon the debris on the magnets it was due for a clean out. In the future, if ever done again I will just drop pan and clean magnets. The screen was a waste of time and money. Been using Amsoil synthetic ATF since 25,000 miles on transmission.

swschrad

the magnets perform a valuable service, picking up all the little flash, wear, machining, and oopsie steel that the transmission had in it. these little knives didn't get a chance to slit the filter, get in the clutch plates or the valve body, and foul things up. really ought to brush and flush these iron filings off the magnets... either in or out of the pan.. to insure you have done a complete job. I seem to remember the old GM '76 shop manual I had with my Buick insisted on that step.

opera_house_wk

I always put four in when I drop the pan the first time. My 97 Explorer had one (plastic sheet magnet) installed I guess from the factory and added even more. These catch the really fine particles that a filter won't pick up. I like the ceramic ones that they sell (Radio Shack). They loose their effectiveness as the material builds up so it is wise to clean them. They clean the oil mostly when you are parked over night. There is a lot of turbulence in the pan that they can not compete with. I dropped a pan one time and found 3 needle bearings in the filter. Quite a flow to suck them up.

mdey

My system has been to have the pan dropped, the filter replaced, and the torque converter rotated and drained at the first service (about 25,000 miles). At 50,000 miles I have the flush done, then back to the pan drop at 75,000, and so on. I've done that on my last two cars and it seems to strike a balance between getting all of the fluid out and getting the filter replaced from time to time.

I got 108,000 out of a Windstar before the engine gave up, but no trouble with the transmission. I have 135,000 on an Explorer on the original transmission, no troubles there either (I even pull a 2,000 pound trailer with it from time-to-time). I plan to stay with that system until it lets me down.

cmack4

My local GM dealer uses the BG PF5 for Transmission Flushing with Synthetic ATF.

http://www.bgprod.com/autodrive.html

Anyone have any experiences with it? How well does it work? They recommend the service every 25K and they drop the pan/change the filter at 50K and 100K. Price quoted is $119 per flush, and they'll throw in the pan drop/filter change for free at the 50K and 100K service.

stans40

3 weeks ago bought a new 2002 camry. Was there when they did the dealer prep. When he checked the ATF after it had been driven a few miles it was still at the cold level. He added some fluid(I don't think it was more than 1/2 quart) to get it up to the hot level. When he checked it was at the first notch of the hot level so I said leave it there since I though it might go up a little more since it had not been driven that far. I then noticed he was using Shell dexron II III ATF. I then went to the parts department and bought some Toyota ATF which also said Dexron II III so I thought every thing was OK. When I got home and looked at my owners manual it said use only T-IV ATF. I called the dealer(50 miles away) and asked if this would hurt my car. The parts man didn't know about T-IV fluid and transferred me to the service department and he didn't know anything about T-IV fluid, but said he didn,t think it would hurt the car . He said I might want to change the fluid at 15,000 miles to be safe. I told them to check on it and let me know. Didn't hear anything from them so I called Toyota customer to ask them if it would hut my car, but the lady couldn't provide any useful information. Then I called the dealer owner and he said he would check on it. He had his customer service man call me, and after he investigated he said they poured the T-IV out of big jugs(I checked and these are 4 liter containers or a little over a gallon) into the quart Shell containers. He also said the man I talked to in service was the assistant and hadn't been briefed on the T-IV. So they aren't going to admit that they put the wrong fluid in my car. So my question is still will putting about 1/2 quart of dexron in my camry do any damage. Even if I drain it it will only get out half the AFT. I think it has a drain plug so they won't have to pull the pan. Any information on this problem will be appreciated.

armtdm

Never heard of this new fluid? Toyota specific like Honda?

armtdm

Never trust anyone to properly fill your ATF. 99.9% or shops cannot take the time to drive the car 10 miles (as the manual recommends) to heat the fluid up and then check it. You are better off having it underfilled then heating it well and checking yourself and adding up to full. Much easier then an overfill and having to syphon some out etc. I have yet to see any shop get the level correct, independent or dealer. they just do not take the time to do it correctly, Letting it idle ten minutes does not do the job, it has to be driven 10 miles at least, especially if temperature is cold outside,