Changing Automatic Tranny Fluid

[theKnifeArtist]

so it's time for me to change the tranny fluid. what's the best way to do it. i was thinking to drain it from the drain plug and pour some new stuff in, but my friend said that was is risky, so i should put a tube in the dipstick hole, suck it out...go through the gears(automatic remember)..and then refill it.
what do you think?

 

[Nick M]

http://www.cygnusx1.net/supra/library/TSRM/ma/MA_12.html

edit: I didn't even read the whole post. It is risky to drain fluid out of the whole that the engineers put there to drain from?

That is what the drain plug is for.

 

[theKnifeArtist]

thanks! thats exactly what i was lookin for

dammit, the simplest task is now really difficult that i dont live at home but rather in a townhouse with a lack of tools and maintance people that are out to get me if i try to even open my hood in the parking lot.

 

[iwannadie]

thanks! thats exactly what i was lookin for

dammit, the simplest task is now really difficult that i dont live at home but rather in a townhouse with a lack of tools and maintance people that are out to get me if i try to even open my hood in the parking lot.

load the supra up with all the tools(barrowd i guess) and go to a local walmart at 2-4am. do all the work right there in the nice parking lot. or any store really, when i go to the 24hr auto zone there is always a few cars out there up on jacks.

 

[Nick M]

There are specific funnels for ATF. They have a very wide throat, and very thin lower spout to fit in the small tube. See your local autoparts store.

 

[koulee]

You can, but you'll only get at most 2 quarts out of the 8 or so quarts in the tranny. After doing this, I would just do it every time I change the oil so that at least some of the fluid is fresh.

 

[iwannadie]

You can, but you'll only get at most 2 quarts out of the 8 or so quarts in the tranny. After doing this, I would just do it every time I change the oil so that at least some of the fluid is fresh.

thats what i was told too. however when i did mine i think pretty much All of it came out. i wasnt expecting it either, over flowed my drain pan.

i drained it when the car was very hot, maybe that made the difference.

 

[americanjebus]

this was covered already in the faq but i got the most out by disconnecting the oil lines that run to the radiator, the left/driver side of radiator has the hose where the oil comes from i put that in a container turn the car on for about 10 seconds or untill the fluid stops coming out, (only about 2-3 quarts will come out then it will stop coming out), let it pour out, measure how much came out and pour the same amount of new fluid down the dipstick, do this 2-3 times and you'll get almost all of the fluid out instead of just diluting it.

 

[koulee]

this was covered already in the faq but i got the most out by disconnecting the oil lines that run to the radiator, the left/driver side of radiator has the hose where the oil comes from i put that in a container turn the car on for about 10 seconds or untill the fluid stops coming out, (only about 2-3 quarts will come out then it will stop coming out), let it pour out, measure how much came out and pour the same amount of new fluid down the dipstick, do this 2-3 times and you'll get almost all of the fluid out instead of just diluting it.

Yeah see, I thought I would be able to get more out from the drain plug if I kept the motor running for a few seconds, but all I could still manage was some 2 quarts. I guess the tranny needs new fluid to push out the old fluid.

I did calculations on this actually. The tranny holds about 7.6 quarts, and draining from the drain plug removes about 2 quarts of fluid. If we assume uniform mixture of the new fluid with the old fluid before draining:

1st drain: 73.68% old fluid or about 5.6 quarts
2nd drain: 54.29% old fluid or about 4.12 quarts
3rd drain: 39.94% old fluid or about 3.03 quarts
4th drain: 29.38% old fluid or about 2.23 quarts
5th drain: 21.61% old fluid or about 1.64 quarts
6th drain: 15.51% old fluid or about 1.18 quarts
7th drain: 11.43% old fluid or about 0.869 quarts
8th drain: 8.42% old fluid or about 0.64 quarts
9th drain: 6.2% old fluid or about 0.472 quarts
10th drain: 4.5% old fluid or about 0.348 quarts
11th drain: 3.37% old fluid or about 0.256 quarts
12th drain: 2.48% old fluid or about 0.188 quarts

If we only consider the old fluid at the start of this process, after the 12th drain only about 0.188 quarts of it remain inside the tranny. The only thing is, we need to drive the car around long enough to allow the transmission to mix the new fluid with the old fluid uniformly so when we do drain the next time, the mixture of the fluid that is drained is also uniform.

So by looking at the numbers, if you want new/fresh fluid in the transmission, draining once a month would be sufficient to replace 97.52% of it within a year.

 

[theKnifeArtist]

oh and another question, its there a tranny fluid filter inside the pan?

 

[JustAnotherVictim]

Yes.

 

[theKnifeArtist]

how come the tsrm makes no mention of it?

 

[JustAnotherVictim]

??? beats me.
It is there though.

 

[theKnifeArtist]

those sly foxes.
dammit i didnt feel like dropping that pan. oh well.
thanks for the information.

 

[suprarich]

It is not really a filter, it is a screen and rarely needs service. It you feel it does, it is a manner of just cleaning it.

 

[americanjebus]

Dropping the pan isnt that hard, just be carefull with all the little bolts because they dont look all that strong. The part numbers for the oil screen and toyota orange oil pan gasket material are in the pics.

 

[koulee]

Aye its called an oil strainer. And americanjebus is right, becareful when you torque them down cause you can strip them and they will be a pita to fix.

 

[theKnifeArtist]

another question.
i bought dexron III by accident cuz when the guy at the autoparts store handed it to me i thought i was just dumb and there was no such thing as dexron III and he just corrected me when i said II.
so anyways.
can i use this fluid for my auto trans?
its a no right?
whats the difference anyway...

 

[theKnifeArtist]

anyone?

 

[koulee]

Dexron III supercedes Dexron II. Yes its alright to use it in there.