My friend has an 01 gmc sierra z71 1500 with the fully eletronic 4wd system(3 buttons) and last desert trip it stopped working. Both actuators move and sound fine when engaging 4x4 but there is no 4wd. Only thing he did was replace front axle seals so i dont think that would of caused the problem. Is there any special alignment of any parts up front or could the transfer case actuator be binding up or gone bad? we think its the transfer case actuator but 4 low works (front tires dont engage but it does shift into 4lo). We've also checked the front axle actuator and it seems to work also.

90% of the time it is the switch panel itself. Check with the dealer, they probably have about a half dozen of 'em in stock

im going to agree with post number 2. i have a previouse co-worker that had the same problem. and it turned out to be the switchs went bad, as switchs can do at any giving moment. also check all grounds, good luck, sucks to have a 50 thousand dollar truck that doesnt work. blah blah blah

i was looking at a new truck (all the big three use buttons) and i do not want a computer to control what only needs a lever.

i will wait till they start making the trucks were one can work with it and not have to replace a button, computer just to make it work.

not holding my breath.

only problem is that is the switch panel doesnt fix it then you probably cant return it to the stealership correct?

Has the front axle actuator been checked? The t-case might be shifting just fine but if that actuator isn't engaging the axleshaft you're just spinning the spider gears in the carrier. I don't know what the best way to tell if it is engaging is other than to jack up one side in the front with it in 4wd, pull the driveshaft from the pinion, and spin a tire to see if the pinion spins.

the front actuator moves just fine(checked it out of the front diff). do they get weak maybe?

i was looking at a new truck (all the big three use buttons) and i do not want a computer to control what only needs a lever.

i will wait till they start making the trucks were one can work with it and not have to replace a button, computer just to make it work.

not holding my breath.

Look at a Dodge and I assume for still offers it as a special option or they did in 05.

alright... after finally getting around to fixinf the 4wd system. we tried a new front acuator and that didnt work so we got the entire truck in the air and the front driveshaft is spinning but the front housing seems like its just completely disconnected from the wheels and driveshaft. we did accidently put an lsd additive in it, could this be causing the problem? we tried draining it all out and spinning it up again with just no fluid to maybe make it catch but its still seems disconnected. Any suggestions?