How to Drain/Refill Automatic Transmission

Just do the Temp Check Mode in your garage. No need to drive.

It'll warm up to the Check Temp in a few minutes.

 

PRO TIPS FOR YOU NEWBIES AT THIS

Remember making mistakes is how you learn. So I'm learning, okay? Like... a lot.

Did the temp check thing this morning, it went correct. Was taking awhile so setting up to install my U bolt flip kit, periodically checking the light. Hey it's solid! Time to check level check plug.

Plug out, no draining. Gotta add some I guess. Time to remove the top fill plug (see? IM LEARNING DAMMIT)

Everything is hot as hell, wearing a welding glove and it's taking so long it overheats. Welp. Shut it down. Didn't put the level check plug back, didn't think I needed to.

SPLOOSH out goes what looks like a quart.

Remember kids, stay in school, don't do drugs - and don't be like me.

 

Also hey Toyota next time... a dipstick. Just... do that. God only knows it would help your stealership techs out.

 

So I just did mine this am along with the transfer case. Did rear diff and power steering last weekend.
Found a broken spring rear drivers side also.
Anywho it was warm maybe not warm enough?
But when I pulled the check level plug probably a 1/2 quart fluid came out?
I’d already made sure the fill plug was ready to refill.
Anywho pulled the drain plug didn’t loose any fluid 80oz or 2.5 quarts in my catch bucket. Put same amount back in?
Truck has 143k on it and I’d say most fluids were original.
ATF was pretty dark, rear diff fluid was nasty and transfer case was dark was surprised at color of it.
Front diff was replaced before purchase so I’m gonna check fluid level.
Brake fluid replaced due to idiots at stealership not tightening a caliper broke a line and lost brakes.
Rad fluid tests good for ph and freeze boil points. Just purchased last winter and getting to some neglected maintenance here in Vt.

 

This is all fine because now you can put together a writeup on your serendipitous discovery of a new drain and fill methodology...well, a new drain methodology at least.

Sounds like something I would do.

I bought some extra WS today because I’ve decided to do a few DAFs and get as much old fluid out as possible. So I was getting excited. Now, reading about the shenanigans, it’s more of a gird up for war mentality. Will I dump multiple quarts on my driveway? Will I get a second degree burn on my own exhaust? Will I break any bolts when I drop the tranny pan? An exciting time to be alive.

 

Yeah I was surprised that turning off the engine caused a giant dump of fluid. That still doesn’t make sense in my brain, transmission’s are crazy though. And I haven’t busted any bolts yet…

 

I’m assuming while the engine is running, that fluid is being pumped through the transmission. Once you kill the engine gravity takes over and a fair amount drains back into the pan...

 

Or, if you forgot to scoot the pan back over...

 

I think I just wasnt expecting the fill level plug to behave differently under load compared to turned off. That still boggles my brain a little. I know not to do it NOW of course. I just don't get why.

 

See Hook78 above. The transmission has a ton of "nooks and crannies" and when fluid isn't being pumped through all of them, well, it can only go down...

 

I guess I was expecting that fill level plug to work either on or off, guess it does not.

So the thrilling conclusion - after sitting for about 5 hours, maybe a little more, I tried it again. Threw it in temp check mode and the light stayed on solid. So, right at optimal temp immediately. Goofy! It's just under 100 degrees outside but still. Go figure.

I pumped in what I thought I had lost in the "incident" before starting her up. Popped the fill level plug and it did drain out some. Maybe 1/2 cup at most. Closed it up, double checked and the AT OIL temp light was still solid. Calling it done!

 

And after all that while I'm cleaning up, I look down... and... is that the washer from the level drain plug? Yes. Yes it was. At least this time I started it up first, before doing that AGAIN

 

Dude, I feel you! Seems like EVERY SINGLE auto/moto project I get into goes like that! Especially the ones that I do just infrequently enough to "think" I remember exactly what to do... only to be reminded that, no, no I do not... lol!

 

The flip side to all of this is the diffs and t-case were all stupid easy. I’m glad I got to learn all of this. Slowly making me braver with mechanic work. I’m eyeballing those 3 degrees offset cam gears now…

 

There is factory pan that uses a dipstick - it was used on the Tundras. I may have the part number around here somewhere.

Also, there is an aftermarket pan which both holds more fluid and has a dipstick. https://www.yourcovers.com/pml-toyota-a750e-a750f-deep-transmission-pan.html

 

That would start an entirely new debate about when is the proper time / temp to check the level though

 

You would probably still want to do the temp check procedure. Just because I made it look hard doesn’t mean it is. What’s the saying… life is hard. Even harder if you’re dumb!

 

Agree.

But - once you set the level with the temp check procedure, you can check the level on the dipstick. It is now your reference point - do not pay attention to the marks on the dipstick, make your own.

Then, you can check the level using your temperature conditions and your mark on the dipstick. While perhaps not "exact", this is a quick indication that you may be low on fluid. Then, do a fill the "correct" way.

This method offers peace of mind between drain and fill procedures.

 

This method offers peace of mind between drain and fill procedures.[/QUOTE[/QUOTE]

What procedure did you use on your transmission?

 

Hit a little stumbling block in the plan today as I was verifying that I have everything I need. Will be draining the fluid and dropping the pan first, to clean the screen, pan, and magnets, and replace the gasket.

The bolts attaching the pan to the case have a 65 inch pound torque value, lower than the range my wrench covers. Only one I can find in the area is at Harbor Freight and costs $100. So much for saving money.