At around 85,000 miles my 1995 Z28 needed a tranny rebuild (4L60E) so I took it to a local shop who charged me $1,300 for a full rebuild. I expected to get the car back and have it shift like new... it shifted soooo sloppy.. I took the car back to him 4 times and he never improved the sloppy shifts. He just put a new throttle sensor and stuff like that on it because it wouldn't shift at all at WOT. Then he told me so don't go WOT.. well thats bull but ive been driving the car like a grandma until I could figure out what to do next to make this right and today my top speed was 25 mph because it slips and wont shift at all. ANY ADVICE??!? i don't trust this stupid tranny guy and i dont trust automatic transmissions anymore. what all needs to be changed when converting to a 6 speed? do i have to swap computers? please any help would be nice

 

Well, my tranny blew because I was putting 380+ (mental math, but that sounds about right) at the crank through the tranny. Clutches got fried after a run at the strip. First the tranny stopped shifting WOT, then about 2 weeks later it had trouble shifting under heavy throttle, then a week after that it wouldn't shift out of 1st gear, then (2 hours later) I couldn't get the car moving below 4K.

Sounds like your tranny guy isn't rebuilding your trans properly... or maybe (assuming your screen name relates to your displacement) your motor is just annihilating it?

 

Man it just burns my butt that there are so many incompetent people that claim to be tranny builders.
My buddy Tom went thru a rebuild and 4 attempts to make it work right then gave up.
He bought a manual, an instructional video, and the parts that he thought he would need to do it himself.
Well 2 trips to the track, about 16-18 passes at 12.5 @ 108+ and it's working great.
What does that say about the self professed pros?

Make the guy fix it right. As for whether it will last? My stock one has 500 passes on it and the last 200 have been with a big converter running low 12s at 109-112mph.

 

Yeah, don't blame the tranny, it's the repair "technician(s)". Competent people can rebuild them where they will work correctly. Get your money back or make them fix it right or take them to small claims court, then take the car somewhere else to get it fixed.

 

the same exact thing happened to me man. the difference between your problem and mine was that mine didnt cost 1300 it was only 900. I am currently switching to a t56. i think it will be better than the 4l60e anyways. well good luck!