The contact owns a 2006 GMC Sierra 1500. While driving various speeds, the vehicle made a loud clunking noise when the accelerator pedal was depressed. In addition, the vehicle shifted hard when switching gears. An independent mechanic diagnosed that the valve body inside the transmission was defective. The vehicle was not repaired. GMC of plattsburgh, New York (518)-563-2000 was made aware of the failure and stated that there was no recall on the vehicle. The manufacturer was made aware of the issue and provided the contact with case number: 8-3309303524. The failure mileage was approximately 20,000. Updated 12/13/2017 consumer stated does not shift down going down hills half to ride brakes at all times. Light did not come on when we had trouble with ABS cable to wheel bearing, you lose brake power. Also transmisson does not shift down. Updated 7/18/18

- Keeseville, NY, USA

1.rusted brake lines blowout.fortunately mine happened in a parking lot, not on the turnpike, and requiring an emergency stop. 2.clutch master cylinder plastic mounting flange separates when clutch is depressed, disabeling std.transmission.on residential street.

- Monroeville, PA, USA

2006 GMC sienna. Consumer writes in regards to transmission gear shifter sticks/ grinds when clutch is depressed. The consumer stated he had trouble shifting the five speed transmission from the time, he purchased the vehicle. It would stick in gear when shifting, move with the clutch depressed when he started it in gear, and scrape when shifting between gears. Overall, the clutch was not disengaging/ the dealer claimed the vehicle was self-adjusting and there was nothing that could be done. The consumer received information about an incorrect clutch master cylinder being installed in 2006 Sierra's.

- Jarrettsville, MD, USA

The contact owns a 2006 GMC Sierra 1500. The contact stated that there was an unknown substance leaking from the vehicle. In addition, the brake lines were rusted and had holes causing it to potentially fracture. The vehicle was taken to a dealer, who diagnosed that the brake lines needed to be replaced. The vehicle was repaired. Additionally, the contact stated that there was a loud noise coming from the vehicle. The vehicle was taken to an independent mechanic who diagnosed that the transmission needed to be replaced. The vehicle was repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 90,000. Updated 12/10/14 updated 9/29/2015

- Pilot Mountain, NC, USA

We were in a storage facility parking our camper when I got out of my GMC truck...I left it running in park because it was so hot outside...while I directed my brother to put the camper in place with his vehicle. This took approx. 20-30 minutes when all of a sudden my truck is going in reverse all on its own running into some boats that were stored there. Wth!! my truck got rear end damage, bumper damage, light broken and my topper was messed up as well....along with the boat trailers that it hit! was there any recall with this problem? I bought this truck about 2 years ago with only 29,000 miles on it and it still only has 38,000.

- Metairie, LA, USA

2006 Sierra -75000miles clunking in drivetrain when trans. Shifts rearend clunks and jumps in and out when diff lock is needed chatter in steering column engine light comes on when down to 1/2 -3/4 tank (everytime) refuel it goes out dash lights for the radio buttons slowly going out dash lights on the slider for heater controls going out very poor mpg 12-13 on a good day! sure would like to have all the recalls and bulletins taken care of! note to myself!! never purchase a GMC again!

- Bird Island, MN, USA

The contact owns a 2006 GMC Sierra 1500. The contact stated that when driving at various speeds or sitting idle in park, the four wheel drive switch would intermittently activate and independently shift into low drive. The vehicle was inspected by a dealer who informed the contact that he would need to replace the module in the transfer case. The vehicle was not repaired. The VIN was unavailable. The failure mileage was approximately 36,000.

- Richmond, VA, USA

I own a 2006 GMC Sierra. I purchased this vehicle from a relative (70 year old woman) and it has 22,000 miles on it. I have just had a mechanical issue begin. When slowing the vehicle to approximately 5 mph, the vehicle ABS activates and the truck thrusts forward. I was advised by a mechanic that this is a failure of both front wheel hub assemblies. Because this vehicle has so few miles on it I began looking on line for recall information. I am shock how many people have also experienced problems around 20,000 miles, some resulting in crashes. I also learned that the company that manufactures the hub assemblies has issued a recall for the parts unless it was installed by the factory (GM). This isn't right and someone will get injured badly. GM should recall the vehicle.

- Sutton, MA, USA