Transmission Fluid Drain and Fill

My son and I our chasing down some leaks in his 98 Tacoma that we purchased about 6 months ago. We are going to change (just drain and fill) the 3.4 auto transmission fluid, but are having trouble getting to the bottom of the best way to accurately check the fluid level. We want to make sure to get it to the correct level after we are done regardless of if it is wrong now.

We have searched the threads (although I am not an expert at that) and there seems to be some conflicting advice. If we check it while warm, running and in neutral the level is very low, if we check it warm, running and in park it is very high.

Does anyone know for certain? I do not have a manual yet. It sounds like some people add about 2.5 quarts after a drain and fill, so that would probably get me close, just looking for direction from the experts. Sorry if this has been asked 100x

 

Here you go!!

 

Exactly what I was after. Thank you for taking the time to find that and respond.

 

If you suspect it's been a very long time since it's been flushed out, it might be worth doing a bit more comprehensive flush. It requires more time and tools, but it's well worth the effort.



I did this on my 01 when I first got it as part of 'baselining' all the maintenance fluids, and it made the auto trans run about ~20° cooler and firmed up the shifting. Just be careful and keep track of your measurements and it should be fine. I plan on doing this again after I drop the pan to clean the magnets and replace the trans filter.

Good luck with the project!

 

OP we like the hear results

 

It was an easy process although now that the fluid is red it is clear that the leak that we are chasing is from the transmission. Unfortunately, there is no evidence of leaking at the pan or the dipstick attachment.

 

pictures?

 

So we did the drain and fill, added 2.1 quarts and then an extra 1/2 quart to try to get the level up. We didn't want to overfill, so after a couple short drives we checked while warm/in park. After adding a total of 3 quarts we are still below the cool mark. This is consistent with the fact that there was at least 3.5 quarts removed when we drained it. I am going to drive it a bit more and then add another 1/2 or so. It is surprising how for off of the 2.1 quarts that it is. Has anyone else had this experience?

 

Now that I have done a bit more research I see that most people are reporting a 4-5 quart drain and fill volume even though the manual says the above. Glad to see this and I will simply add a bit more. Thanks for the tips

 

Unsealed AT FTMFW!

 

did you find the leak?

 

Did you rule out a power steering leak?

 

Just did a power steering flush and screen clean. I don’t think it’s coming from there.

Valve covers are clean and recently replaced. Degreased and sprayed engine. Oil seems to be coming from junction of engine and transmission but it’s surprisingly difficult to view up in there. It is really just accumulating on rack and pinion but leaking from somewhere above that. It’s just a drop a day so I’m going to watch it for a while. Harder to find source than I would have thought. I tried the fluorescent dye with UV light but the old dry oil actually looked yellow too.

As I mentioned in a previous thread, it wasn’t leaking until I switched to full synthetic so it’s most likely engine oil.

I’m taking a break from it but will report back if I determine the source.

 

Shop Manual is not correct, drain & fill is 4 qts. Complete flush is a little over 12 qts. I've done both many many times. 1997 3RZ, Automatic.

 

I’m betting it’s valve covers gaskets