I have a 96 chevy z71! when I bought the truck the tranny was messed up! it had reverse nuetral first n second gears! No drive or overdrive! It would pull off in overdrive shift from first to second and then would just rev up when it tried shifting to third! you could then rev the motor a little and then back out of it and it would shift down into second and continue on! Or start in first and shift to second an drive on! A friend gave me a tranny out of his wrecked 2000 model! It had it was a remanufactured 4l60e from general motors! I installed it and the torque convertor and drove the truck for three months with no problems! then got in it one morning and it was shifting a little funny! I had to gas it a little n back out to get it to shift into drive or OD! stopped n checked fluid n it was half court low!Added half court an had no more trouble for three or four days! And was coming home and it all of sudden would not shift into drive or OD! It is showing same problem as previous tranny! Fluid level was fine! Fluid was pretty red no smell of being or color indicating it being burnt! no code showing! I drained pan and removed it and pan was clean! was told it could be shift selinoid so replaced it new filter and fluid and still same trouble!HELP PLEASE!

 

had the same proublem with my 96 k1500 cost me 1400$ to get it rebuilt no proublems yet as for y the guy that rebuilt mine sead there was something in the frunt of the tranny and that if u didnt put the tranny in just right it would go out

 

I put tranny in myself. Any idea what it is that will make it go out so I dont make same mistake twice

 

Sounds like the forward sprag went.
I just went through a replacement for this very problem.