Engine gaining oil, trans loosing

[Mike Mac]

My '92 XLT transmission keeps loosing oil to the point it hesitates or won't move in drive, "dipstick dry". It will loose about a half a quart per trip of 450 miles. After 3000 miles and adding 1-2qts I found that my engine oil level had gone up at least a quart. Is this a bad front trans seal and rear crank seal? Took the starter off and found no real oil film in the Bell Housing. The engine oil takes on a red tint when just changed. Vehicle has 187K, no puddles. Any suggestions?

 

[lonestar]

I don't see anyhow tranny fluid would get in the engine, unless a tranny line is hooked up to a oil cooler or something. Check the Antifreeze.

 

[JDraper]

From what I remember, that's one of the symptoms of a bad vacuum modulator on the tranny. When the modulator diaphragm breaks, it sucks tranny fluid back into the motor through the vacuum hose.

 

[lonestar]

but wouldn't it burn the tranny fluid, rather than fill the crankcase

 

[Mike Mac]

Thanks, good info on the vacume modulator.
I found USATRANSDOCTER.COM is saying the same;
A4LD
This transmission is a rear wheel drive 4 speed automatic. Common symptoms are erratic shifting, hesitating going into gear and losing transmission fluid without a trace of a leak. You have a modulator on the passenger's side of the vehicle pointing towards the driver's door. Pull the rubber line off the modulator and see it trans fluid comes out of the line. Now, if it does your modulator is no good.

Hopefully I'll discover oil tonight at the modulator.