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Old 01-21-2013, 05:24 PM
snowsled7 snowsled7 is offline
The Ornery Old Man
Location: SW Mountains
Join Date: Mar 2012
Posts: 980
Mein Auto: GTI
Originally Posted by Larrick View Post
Isn"t there a standard amount of ATF which should be in the transmission? And if that amount is put in after the sumps are back in place. why not run the engine with the transmission engaged and wheels off the ground
to speed up the heating of the ATF?
There is a standard amount if you could drain the whole system. Most of the trans fluid is in the torque convertor. If you can't drain it, it stays in the system and all you can do is guess. You can measure what you remove I guess.

What is the purpose of running through the gears with your foot on the brake? The transmission is not moving.
Does this engage the pump to circulate the fluid?
Why would the fluid heat up at all, when nut under driving conditions?
With your foot on the brake and the trans in gear, the engine is running against the torque convertor. This will heat the fluid up more quickly. The convertor is like two fans blowing against each other in a fluid bath. The fluid heats when the fan on the engine side is pushing against the stationary trans side fan.

Seems to me that the $100-120 is costs to have the fluid exchanged at a shop would be a lot easier and cleaner than trying to do it yourself. Good Luck
Current ride... '13 GTI Wolfsburg
BMW's from my past...
'92 535i/5 '89 325ix/5
'98 750iL '86 325(e)/5
'95 740iL '84 318i/5
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