Vehicle is a 4WD model, equipped with electronically controlled transfer case. The control only works intermittently. Several times I have been caught in a snowstorm and unable to use the 4WD. This is a serious safety issue. I had the control repaired once, but the problem quickly returned. I am told this is a very common problem with 4WD Chevrolet and GMC trucks, for many model years.

- Ebensburg, PA, USA

I drive a 2004 Chevrolet Suburban Z71. When I am driving down the road the transfer case shifts into neutral. I didn't touch the transfer case controls or anything it just goes into neutral. It works just fine in auto 4WD, 4hi, and 4lo. This only occurs while driving in 2hi. I haven't gotten anything fixed yet because electronically it appears that everything is working normally. The mechanic said that he would have to take apart my transfer case and I cant afford it. I was wondering if this was some kind of manufacturer defect or something because it doesn't do this all the time. The problem occurs intermittently. I have never driven this vehicle off-road or have had to use the 4WD for anything. It just seems odd because this vehicle doesn't even have 70000 miles on it. I would think that something like a transfercase would be built to last a little while longer. It hasn't caused an accident yet but has come close a couple of times like when it fails in the middle of an intersection.

- Altamont, IL, USA