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tranny leak

if the torque converter hub to pump seal is continually ejected from a th700r4 trans, excessive pump pressure is leaking into cavity behind seal. this problem was addressed in the early 90's with drilling a relief hole from cavity to oil return passage to pan. The reason the leak happens is that machining tolerances were too wide at pump to trans case mating surfaces causing high pressure leak. I am not sure where to get the specific info anymore...I have'nt fixed autos professionally since 1999. I know there was a boat load of tsb's for this problem...so a gm dealer is a good place to start.

Also, you were describing a high, late shift condition as well at a shift flare, most likely cause is a lack of hydraulic pressure on forward clutch drum (read SLIPPING). Trans really needs to be disassembled and have clutch packs inspected and restacked with new friction discs minimum.

Good luck with your "technician" to make the right choices and repairs.

Crank
 
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