Driver's side front wheel assembly separated from the vehicle. It was hard to tell exactl what happened but I am told that it may have been a ball joint failure. I was driving in the middle lane on the highway with cruise control set to 70MPH. All of a sudden, my truck jumped up and my truck starting pushing towards the left median. I thought I had a tire blow out. Luckily there wasn't anyone in the left lane at the time and I was able to get to the grassy left median. If there was another vehicle in the left lane and or if the left median wasn't grass, this would have caused a major accident as I has no control over where the truck was going. When I got out I saw that my entire wheel had separated from the vehicle and it was on its face under the truck. I did not hit a pothole. There was no prior indication that anything was wrong with the assembly. A tow truck was called and brought the truck back to their shop. The assembly had to be replaced, (ball joint, axel, steering control arms etc.). I called my local GMC dealer and they have nothing being reported of this issue but when I looked online I've seen multiple reports of premature failures of ball joints. Total repairs so far have been $3,400 and I still need to replace a cracked rim. Repairs will be over $4,000 when all said and done.

- Lunenburg, MA, USA

At 50,000 miles the upper control arm/ball joint on the driver side came apart with no warning causing considerable damage to the suspension, tires, wheel, and front bumper. About two months before at approximately 48,000 miles the passenger side control arm/ball joint came apart again with no warning. Warranty has just elapse and GM has denied any responsibility and will not cover any of the repairs. This could have easily been catastrophic if we would have been on the freeway. This is a Safety issue! This truck has the aluminum upper control arms which my opinion for what its worth is the problem. I have no clue at this time how we are going to be able to fix this. Even when it is fixed we will never trust it.

- Newport, MI, USA

Ball joint separated from control arm while driving. Vehicle was undrivable had to be towed.

- Shepherd, MI, USA

Transmission slipping turning corners at 5 mph, transmission slip take off at hill stop sign, transmission hard shift 2nd to 3rd gear intermitted and vibration 45 mph to 55 mph

- Manson, NC, USA