I have a 1995 chevy k1500 with the 4l60e tranny and it wont shift trough the gears unless the let off the gas then it will shift , replaced the tps, map and just replaced the entire valve body solenoids and all but still doing it what is causing this ?

Possibly the pressure switch inside the transmission. Years ago I had a Corvette with a transmission that wouldn't shift unless the throttle was, literally, pushed to the floor....basically redlining the tach, forcing the computer to make the tranny upshift. I replaced that pressure sensor and all was good again. Probably saved my life.

thats was replced as well when i did the valve body

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