While driving down a mountain road with a 5th wheel attached it appeared that the rear brakes on the drivers side were smoking, I pulled over to allow it to cool. We found a GMC dealership and proceeded there very slowly stopping a number of times to allow the brakes to cool down. 2 miles short of GMC, there was a loud pop and a tire had blown. We pulled over and while calling roadside assistance noticed fire under the truck. We put it out with a fire extinguisher before the fire department arrived. We were towed to the dealership. The brake caliper came apart, the rear axle broke (possibly melted from heat and fire?). GM initially stated 4 days to repair, now they they are saying 3 weeks as they have to build a new axle. If we had not had the extinguisher the truck, rv and meadow would have all gone up in flames and who knows the disaster that could have occurred if this happened on the mountain road. This vehicle only has 17,000 miles, 11 months old and has had all routine maintenance performed at GMC dealers. I have more pictures but am unable to upload them.

- Walnut, CA, USA

Purchased a new 2017 GMC denali 3500. The truck came with 4 michilen lt 265/70R18 A/T2 tires on it. The spare tire is a Goodyear tire. Page 401 and page 402 of the owners manual states: Mixing tires of different sizes, brands, or types may cause loss of control of the vehicle, resulting in a crash or other vehicle damage. Use the correct size, brand, and type of tires on all wheels."

- Waukesha, WI, USA