YotaTech Forums - Auto Trans. Issue

It's not mine, it's my friends. The truck shifts fine and and goes into drive and reverse o.k. But if he gives it any more throttle then the stock stall converter limit, it starts slipping like a bad clutch and too much power. Even if you shift it manually, it'll do it in second and third. It does it in reverse too. I told him to give it gas while on the brakes when in reverse and the same thing. The truck will try to move in reverse but with very little power. Any more throttle then what will spool up the converter and the motor just revvs up. The fluid is good, the level is good, and he hasn't changed the fluid.

Has anyone had this problem?
Could his torque converter have taken a crap?
Or is this the tell tale signs of the inevitable?
Any help is appreciated. Thanks.

OOps, it's a 86, std cab, long bed, 4x4, 4" susp/3" body, 35's, 5.29's.