Bought my GMC in April of this year 2007. Never had to use the 4X4. Unfortunately with 9 inches of snow tried the 4X4 for the first time and it did not work. Took it to the dealer and they said it was the transfer case was not working and needed to be replaced a 600 estimated service.

- Stamford, NY, USA

I have a GMC Envoy 4WD, on 2 occasions the vehicle has locked the gear into 4WD and 4hi. Vehicle will not respond to command to shift gears to normal driving in 2wd. In turn this leads to problem with the vehicle braking system--vehicle takes too long to stop during normal braking. The vehicle also becomes very unstable on the road--keeps shifting sides making hard to keep the vehicle in a straight alignment during driving. I had the vehicle inspected by a GMC authorized dealer in November, 2005 at which point they found out that there was a problem with the transfer case which causes it to break apart. This in turn causes all the other systems in the vehicle to malfunction because it's a computerized system. The transfer case was replaced which temporarily fixed the problem until Feb, 2006 and the same problem recurred. I have made GMC aware of the problem and they referred me to the dealer. On speaking with the dealer I became aware that this is an ongoing problem with GMC Envoy and the dealer is aware of the problem. The only way GMC is resolving the problem is referring customers to the dealer for a replacement on the transfer case--which happens to be the same one that keeps malfunctioning. At this point GMC does not have a different transfer case that will resolve the issue once and for all. GMC is also willing to fix your vehicle as long as it's under warranty but once it's out of warranty and the problems with the transfer case persist, you have to pay out of pocket. GMC is aware of this problem with the transfer case but they are not letting the consumers know.

- Fort Richardson, AK, USA