1998 tahoe trans problem

[tipler1]

tahoe transmision problem

I have a 1998 tahoe 4dr 4wd, I have a problem in the 1-2 shifting , it revs up to 3000-3400 rpms and then skips 2nd gear and goes right to 3rd. hooked it up to the dtc reader and it flashes code po751. had the 1-2 shift silenoid changed but did nothing. does any one have any other ideas as far as a fix?????????????

[Jeremy-WI]

could be a problem with the 1-2 shift valve, bad seals etc

[gurrzt]

Your 1-2 bands maybe shot, stretched and causing the slip.

[GMMerlin]

Originally Posted by tipler1

tahoe transmision problem

I have a 1998 tahoe 4dr 4wd, I have a problem in the 1-2 shifting , it revs up to 3000-3400 rpms and then skips 2nd gear and goes right to 3rd. hooked it up to the dtc reader and it flashes code po751. had the 1-2 shift silenoid changed but did nothing. does any one have any other ideas as far as a fix?????????????

I don't have my shift chart in front of me, so i have to do this from off the top of my head.
Does the trans go into 4th gear? Can you get manual 2nd?
You may have a 1-2 shift valve that is sticking, or the 2-4 band is not applying.
You can check the 2-4 accumulator for a cut seal or broken spring.
Maybe, the PCM is commanding the 1-2 solenoid to apply, but the wires to the solenoid are open or grounded not allowing the current to flow to the solenoid

[Rodie40]

I had problems with hard shifting and had my tranny rebuilt for $1500 and the problem is still around? what else could make this problem happen?

[Jeremy-WI]

Rodie, you probably need some valve body work done. Do a search for P1870

[Rodie40]

Well, truck went back in this morn. Builder says could be a bad solenoid. will find out today.