08 Sierra Randomly won't shift out of first gear, and no speedometer

[Johnnyrich10]

Hey all, 

My 08 Sierra occasionally won't shift out of first gear.  it only happens every once in a while.  When it happens it won't shift until I come to a complete stop, then goes back to normal.  When it happens the speedometer also does not work.  Anyone have any idea what is causing this?  I have a programmer and no engine light and no codes are showing up.

 

08 GMC Sierra 1500

5.3l All Terrain Z71

 

Thanks,

 

Johnny

Edited August 16, 2021 by Johnnyrich10

[Johnnyrich10]

Anyone have any ideas?

 

[Peej]

did you ever figure this problem out? i have the same thing going on. if you stop and turn either direction it will randomly get stun first and no speedometer. come to a complete stop and 

[Peej]

did you ever figure this out? I'm dealing with the same problem. only happens after stopping and making a turn, no speedo and stuck in first gear. come to a stop in start again its fine for a while.

[Autocop]

It wont shift because it doesn't know how fast it's going. You need to figure out why the speedometer isn't working and once you fix that, you won't have any moire shifting problems.