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Trans fluid

transmission fluid in air filter, connecting tube, throttle body, and oil pan, 92 delta 88 3.8 135k, smoke on start up, and sometimes while driving, 1 1/2 pints daily, oil must be drained every so many hours of running.

The vacuum modulator diaphram on the transmission has ruptured and tranny fluid is being drawn into the engine through the vacuum hose. Look for a canister on the side of the tranny with a vacuum hose attached. Remove the vacuum hose and if tranny fluid runs out, replace the vacuum modulator on the transmission. Oh! And don’t lose the pin that comes out with the vacuum modulator.


The transmission in a '92 still uses a vacuum modulator?

with my fords, this is when that happens. need to check that out. ( my 92 explorer has a vac modulator , don’t know about olds. )

Yes it does.


That repair guide covers '86 - '99. I can see an '86 having a vacuum modulator, but a '92? Even my '89 Suburban had an electronically-controlled transmission (yes, I know it’s RWD and the OP’s car is FWD). Maybe Transman can give us a definitive answer.

But there’s also no other explanation of the OP’s problem if there isn’t a vacuum modulator…

You got it!


Yea Bob. 92 uses a vacuum modulator. 4T60