So here it is...
2004 Avalanche 2500 with 160k miles
Winter 2012 with 120k miles transfer case disinegrates.
Trans shop replaces.
10 months later new transfer case under warranty.
Winter 2013 "service 4wd" indicator lights up when I used 4x4.
Came and went for a year. 4x4 always worked.
2 weeks ago I hear machine gun fire from under truck while plowing.
Slip yoke spun out.
Trans shop replaces front driveshaft and says he can warranty transfer case again.
There was nothing wrong with it, but why not?
He replaces transfer case as well as encoder motor with sensor.
I get it back and it will go from 2wd to 4wd and back one time then buttons do nothing. Shut it off and restart and again 2wd to 4wd one time.
I replace switch in dash as well as 4wd module.
Same result for 2 days, then today start it up, lights on switch flash on start and then switch goes black.
I have 2wd only
I cleaned transfer case ground under drivers door. No help.
Any help out there???