2003 4wd random issues

[92__silverado]

Hey guys,
My Tahoe has been having a strange issue of sometimes just slipping into 4-HI. I had read that the buttons for switching between 2wd and 4wd were notorious for going out, so i replaced it with a Dorman replacement.

While testing the button the truck got stick in 4wd low. When pressing another option the light would just flash and the truck would stay in 4 low.

I replaced with the old switch, same problem.

I was finally able to get the truck into 4 high and eventually 2hi by removing the TREC fuse, starting the truck, shutting it off, then restarting the truck with the fuse in and pressing 4hi, then auto 4wd, then 2 hi.

So, i have no idea why the truck got stuck in 4-low and as of right now, i still think i have an issue of the truck randomly going into 4-hi.


I keep reading about an encoder motor, and a TCCM but i'm not sure what either of these do, or if they could cause the issue.

Any ideas?

Thanks!

 

[92__silverado]

For anyone else that experiences this issue. it ended up being the transfer case motor. $250 dollars and a few hours later and problems are solved.

 

[new2yukon]

Can the motor b replaced without removing the shaft and would jack stands or ramps be sufficient?