well, my 4wd issue is still with me. snow is coming and i need it fixed.

autotrac pushbutton system. the 4wd light will flash then switch back to 2wd without actually engaging 4wd.

I have verified that the front axle is engaging. I can hear the solenoid unlock the tcase actuator but no movement from the encoder motor.

all the basics have been checked, grounds, conectors, chafed wire etc. a buddy of mine is a GM tech and scanned it with a Tech 2. NO CODES.
He lent me a new encoder motor to try since everything pointed to it. swapped encoders and still nothing. i can shift the tcase with a wrench with the encoder off and all is free.

Is there a feedback signal from the front diff actuator to signal the encoder motor to shift?? maybe that circuit is dead??

is there a 'dual path' from the dash switch to separately shift the front axle and the tcase?? is it possible for a bad switch to shift the axle but not the tcase??

this is driving me nuts.

same thing on my '02. I jacked up all wheels but the right front, put it in 4wd and all would spin. had a friend grap the front left and he could hold it from turning while I was in 4wd. looked under the truck and the front drive shaft was spinning but the wheels were not. found out that there is some kind of clutch materal in the front in for the posi. took it to 3 didderant places before I did anything and all of them said everything was fine. I had to take the service guy to a field to prove it don't work. it was time for a new truck anyways so never did anything else. good luck.

mine is the opposite. the front shaft IS locked to the diff but the tcase is freewheeling.

Did you check the fluid in the transfer case?

Make sure you do not have the "HOLE" in it from the pump housing.

If it is low on fluid, there is not enough fluid to lubricate and allow it to function.

Just drain the case, and see if you have the Block Goo come out.

Then look for the hole.

I checked the fluid. the level is up and clean.

OK, then do a search for the dash switch, it is usually what might cause it?
I read something about the switch, but do a search, it might be the problem since you eliminated one of the problems.

Did ya try pulling, waiting a min, then replacing the 30A TREC fuse in the underhood fuse box and check the 10A 4WD fuse in the IP box. Sounds like maybe your TCCM is a likely culprit since I think it commands the encoder motor. Maybe your pard at the dealership can get ya a new one to try.

tried the fuse deal. nothing.

i was wondering about the TCCM myself.

I was messing around with it at lunch and actually got it stuck in low range after about 6 months of nothing at all.

shut the truck off and turned it back on and now it seems to be working perfectly!!??

weird, i wonder how long until it screws up again??

I was messing around with it at lunch and actually got it stuck in low range after about 6 months of nothing at all.

shut the truck off and turned it back on and now it seems to be working perfectly!!??

weird, i wonder how long until it screws up again??


The next time you really need it! Maybe:rolleyes: