1995 GMC Jimmy transmission seems to be burning oil

1995 GMC JIMMY
101,000 MILES • 6 CYL • 2WD • AUTOMATIC
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1995 GMC Jimmy mileage: 101,000. The transmission seems to be operating correctly but each week when the fluid is checked a pint or so of fluid must be added. There is no evidence of a leak at the transmission pan or anywhere else on the case. The transfer case is also dry. If we park the vehicle on clean paper to detect a leak, there are no drops of oil present even after a long weekend. The engine seems to be running clean with no signs of fouling or blue-black smoke. Where can the transmission fluid be going?

Jan 10, 2011 at 11:50 PM
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Obviously you have a leak somewhere in your transmission. If the outside of the transmission is completely dry, the only other place it can leak is into the transfer case. If this is the case, the seal in between the two has failed. On older transmissions, the vacuum modulator diaphragm would fail allowing the transmission fluid to be drawn into the engine.
Jan 10, 2011 at 11:55 PM
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WRENCHTECH
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Make sure you are checking at the same way every time. The level will normally rise after driving it.
Jan 11, 2011 at 12:15 AM
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DAVE'S BIG BACKYARD!
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if your sure its not leaking anywhere then its sucking it out of the trans modulator valve and burning it.
Jan 11, 2011 at 1:04 AM
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WRENCHTECH
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[quote]if your sure its not leaking anywhere then its sucking it out of the trans modulator valve and burning it.[/quote]

That might make sense if it had a modulator valve but it doesn't.
Jan 11, 2011 at 1:10 AM
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DAVE'S BIG BACKYARD!
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well its sucking out of somewhere.its must have some kind of vac going to the tranny if its pulling fluid and bunning it, that is if its not leaking it (for sure)
Jan 11, 2011 at 1:36 AM
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DAVE'S BIG BACKYARD!
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if its flowing into the transfer case then it has to come out some how when it over fills,i dont no im lost on this one.
Jan 11, 2011 at 2:41 AM