tranny ailment

[blazin_blazer]

i have a 96 tahoe, 4l60e, 3rd started slipping on a trip, i limped it home by pulling it into 2nd and get up speed then shift to OD, it would jump over 3rd and continue to go.
it threw a code, that said manufacturers trans. control, i had it read at advance auto, they said they had never seen the code before and reset computer to no avail.
now i've lost all gears forward and reverse, but only after it reaches operating temp....when i 1st start it, it pulls fine, as engine starts to heat up the trans starts slipping to the point the truck won't move, but only after 10-15 mins. and truck warms up. when cold it will rip and snort after several miles...nothing.
any1 else seen,heard of, or had this problem, if so what was the fix?

 

[dyeager535]

WAG, do these things have a temp sensor in them, and if that is screwed up, once it reaches X temperature, the PCM sees the temp "problem" and starts adjusting the transmission to try and "fix" the issue? Although slipping would make a heat problem worse, perhaps it's a sort of bypass or something.

Cold fluid will be thicker, which would mean more pressure/less leakage initially, but I can't believe if the tranny is shot that the thickness (temp) of the fluid would make the difference between works fine and doesn't work at all.

 

[Slapperbar]

When these get hot, or sense too hot they lock full up,(in each gear) so no slippage and not to generate more heat.

 

[dyeager535]

And I would think even if the temp was reading -20*, it would still allow you to move.

Maybe then it's another solenoid or switch that is failing at warmer temps? Hopefully you'll hear from someone that works on these things regularly or has had the exact problem and solved it.

 

[blazin_blazer]

the truck also reaches operating temp alot faster than usual. i believe it to be electronic...guess going to spend $80 and let dealership run full diagnostic.