ATF drain and refill quantity: FSM myth or fiction + temperature effect...

[Hayes]

When I did my first drain and fill, I did the same--added a couple quarts and then drove around, stopping to check the dipstick now and again. I don't recall what my original refill was--but since then I've just been refilling based off what comes out--close to 5 quarts. Sounds like this may be over-filling the tranny by a quart or so--I haven't checked the dipstick in a while. I've been running like this for a couple years, and haven't noticed anything amiss with my tranny. I'm skeptical that running one quart high on a tranny that takes (15? 16?) quarts could do much harm--but I will be checking my dipstick over the next few days.

 

[corsair23]

OK then, it would seem the best bet is to have it done... Just that I prefer to do it myself to LEARN how it's done (I can always get it done in a shop afterwards)

Anyway I thought it was a 'simple' matter of disconnecting a hose, run the engine and let the tranny flush the old through that hose as you fill it with new fluid...

Thanks for your imput, gray, much appreciated

x2 on what Curtis says...
I did mine myself and I'm a 1 mechanic...there are excellent write ups on how to do it. I did the full exhange because the old fluid was nasty looking (dark, dark red, almost black). From now on I plan to do the drain and fill at every other oil change (extended warranty requires oil changes every 3 months/3K miles) to keep it fresh.

On the flush though it is pretty simple. Do a drain and fill first to remove any gunk at the bottom of the pan. Then take the grill off, disconnect one of the ATF cooler hoses (top one IIRC), attach your own clear hose, put hoses in a big bucket, and have at it.

It is MUCH easier with two people though. One to run the rig and shift through the gears while the other person monitors the fluid coming out and puts fluid in. You can't fill the tranny up with ATF through that tiny fill tube near as fast as it will pump out so you have to start and stop the rig. I found it helpful to mark the bucket I used at 1 gallon intervals so I knew how much fluid was pumped out and how much (initially) to put back in.

On my LX I went through 19-20 qts until I was seeing nice bright red fluid coming out at the cooler.

On a side note, if when you do the drain and fill and your fluid looks and smells good (nice bright red and no burnt smell) then I would forgo the flush - this was the case on my '97 FZJ80.

 

[Truckasaurus]

I've had to add 4-5 qts each time I've drained and refilled...wondered why this wasn't quite a bit more dramatic here in this bastion of OCD behaviors.

Eric, just check the dipstick before you drain, per sound operating procedures, and do the same after you refill.

Remember the dipstick has cold and hot notches, for just this scenario. Fill cold to between the two marks, again using the procedure outlined in the FSM, and then drive until hot, and check.

Bingo bango.

(Or, Bada-bing, bada-boom, if you're from NJ )

 

[e9999]

I've had to add 4-5 qts each time I've drained and refilled...wondered why this wasn't quite a bit more dramatic here in this bastion of OCD behaviors.

Eric, just check the dipstick before you drain, per sound operating procedures, and do the same after you refill.

Remember the dipstick has cold and hot notches, for just this scenario. Fill cold to between the two marks, again using the procedure outlined in the FSM, and then drive until hot, and check.

Bingo bango.

(Or, Bada-bing, bada-boom, if you're from NJ )

the FSM makes it clear that the cold notches are just a rough first shot at it, and that you have to use the hot ones. Just keep in mind that the temp may vary a lot. It's also cute that they mention the temp range you need to do it at, but most people, even here and I wonder about shops, have no way of measuring what the actual ATF temp is...

The whole thing about the FSM (and/or my dipstick) being self-contradictory is just plain weird...

Somebody measured the length of their dipstick (no joke, please ) and the position of their notches (again ) and can post? I'll try to do that too after I recover from SnT...

 

[83bj60]

x2 on what Curtis says...
I did mine myself and I'm a 1 mechanic...there are excellent write ups on how to do it. I did the full exhange because the old fluid was nasty looking (dark, dark red, almost black). From now on I plan to do the drain and fill at every other oil change (extended warranty requires oil changes every 3 months/3K miles) to keep it fresh.

On the flush though it is pretty simple. Do a drain and fill first to remove any gunk at the bottom of the pan. Then take the grill off, disconnect one of the ATF cooler hoses (top one IIRC), attach your own clear hose, put hoses in a big bucket, and have at it.

It is MUCH easier with two people though. One to run the rig and shift through the gears while the other person monitors the fluid coming out and puts fluid in. You can't fill the tranny up with ATF through that tiny fill tube near as fast as it will pump out so you have to start and stop the rig. I found it helpful to mark the bucket I used at 1 gallon intervals so I knew how much fluid was pumped out and how much (initially) to put back in.

On my LX I went through 19-20 qts until I was seeing nice bright red fluid coming out at the cooler.

On a side note, if when you do the drain and fill and your fluid looks and smells good (nice bright red and no burnt smell) then I would forgo the flush - this was the case on my '97 FZJ80.

Noted not once, but twice
Thanks for the excellent write-up!!!

 

[gray]

I agree totally; if you have someone else do it, you need to know that they know how to do it correctly.

I have written about my experiences, at Toyota dealers. ie: using only 6 quarts for a "flush" (at two different dealers), one leaving a cooler hose dangling so that it got up against the crank, causing it to spew,etc,etc.

If I wasn't so busy and living in an area that gets mad at you when you raise the hood in your driveway, I would do it myself. A few days ago, my wacky neighbor
actually took photos (?or videos) of me with his cell phone while I was working on my P401 problem, like no freakin kidding. I'm waiting for the letter.

Can someone out there go over the exact flow or pathway the ATF takes, so that we all know for sure; ie is it: pan-valve body-tranny-pump-convertor-cooler-pan; is that about correct?

g

 

[Juan Derher]

.... and living in an area that gets mad at you when you raise the hood in your driveway, I would do it myself. A few days ago, my wacky neighbor
actually took photos (?or videos) of me with his cell phone while I was working on my P401 problem, like no freakin kidding. I'm waiting for the letter.g

yikes!

Gray~ it may be time to move or try baking cookies for the CCR Nazi's, maybe they'll look the other way.

I've been there, good luck.

 

[tomatopants]

I removed the drain plug today to put in some higher quality ATF, instead of the present economy-bulk ATF fluid that was in my transmission.

I let it drain until there was just a drip every couple of seconds, and I put in 4 quarts, drove it a while, didn't feel right, and I had to add and refill until I had put in a total of 5.5 quarts.


So 2.1 would definitely have caused me some transmission problems.


I have the OEM dipstick, and with almost exactly 5.5 quarts, it's perfectly between the 2 "hot" notches.

And it shifts better.

 

[e9999]

is it the "bus" tranny?

if so, does it also say 2.1 in the FSM?

I removed the drain plug today to put in some higher quality ATF, instead of the present economy-bulk ATF fluid that was in my transmission.

I let it drain until there was just a drip every couple of seconds, and I put in 4 quarts, drove it a while, didn't feel right, and I had to add and refill until I had put in a total of 5.5 quarts.


So 2.1 would definitely have caused me some transmission problems.


I have the OEM dipstick, and with almost exactly 5.5 quarts, it's perfectly between the 2 "hot" notches.

And it shifts better.

 

[tomatopants]

is it the "bus" tranny?

if so, does it also say 2.1 in the FSM?

I have no idea what a "bus" tranny is.


Nor do I have a copy of the FSM. So to answer your questions, I don't know what you're talking about.


I do know that my drain plug had ZERO metal shavings on it, even after about 10k miles since changing the fluid. It made me happy, I always figured that my tranny was going to be the first thing to die on me.

 

[landtank]

here is a link to a thread I posted on this subject. It was after replacing my tranny.