2011 GMC Sierra 1500: sudden unintended acceleration

Filed Mar 8, 2014 · Engine, Steering · 38,958 miles · VA

Started truck up and let idle for two minutes. Upon take off, the traction control light came on and was immediately followed by the check engine light with a message stating engine reduced power. The truck then begins to run very rough and when the brakes where applied it violently and uncontrollably lunged forward. I pulled off the road, turned off the engine, and waited a minute or two. Upon restarting the engine, the check engine light came on but the reduced power message and traction light where gone. After sitting at a light for a few seconds, the symptoms where back, nearly causing me to rearend the vehicle in front of me. I pulled over again, turned off the engine for a minute, restarted and the same results as before occured. Now this happens every time the truck is running and sits in the same spot for more than two or three minutes.

Filed Nov 20, 2013 · Acceleration, Transmission · 90,000 miles · MI

Tl* the contact owns a 2011 gmc sierra 1500. The contact stated that the vehicle was powered on and in park when it lunged forward abnormally. The contact had to jump in the vehicle and depress the brakes to stop it from traveling any farther. The vehicle was taken to a dealer for diagnosis however, the dealer was unable to determine the cause of the failure. The vehicle was not repaired. The manufacturer was not notified of the issue. The approximate failure mileage was 90,000.

Filed Jun 27, 2013 · Transmission · 400 miles · FL

Tl* the contact owns a 2011 gmc sierra 1500. The contact stated that while driving 43 MPH, the vehicle lunged forward and exhibited an abnormal noise. The failure recurred intermittently. The vehicle was taken to a dealer, who was unable to determine the cause of the failure and stated that the abnormal noise was expected with the type of power train in the vehicle. The failure was not reported to the manufacturer. The failure mileage was 400. The current mileage was 11,728.

Filed Sep 2, 2011 · Acceleration · 3,100 miles · MA · 3 injuries

I was going 40mph when I went to stop quick to avoid an accident. I pressed on brakes truck did not slow down then all of a sudden it did down shift but at that the truck lunged forward causing me to clip the truck in front of me.

Filed Dec 28, 2010 · Acceleration · 2,800 miles · TX

Second report - sudden acceleration. 2011 gmc sierra pu truck. On december 20, 2010 I was traveling to visit friends. While on highway I set the cruise control for 70 MPH. I exited the freeway and traveled approximately 5 miles on city streets. Upon entering a bedroom township known for speed traps I attempted to engage the cruise control for 30 MPH. When pressing the cruise control to set the speed I was traveling (30 MPH) the truck down shifted and accelerated rapidly (to 4000 RPM). I immediately tapped the brake and the cruise control disengaged. This is the second time for this truck to down shift and accelerate rapidly. A previous report was made in november 2010.

Filed Dec 2, 2010 · Transmission · 1,500 miles · TX

On november 18, 2010, returning from vacation, driving a new 2011 gmc sierra sle pick up with less than 2,000 miles use, pulling a 24' travel trailer. The truck was in "tow" mode descending a 15% grade hill at approximately 45 MPH. I was not accelerating when the truck down shifted itself automatically from 5th to 3rd gear and the engine accelerated to 4000 RPM. I applied brakes and truck shifted back to 5th gear. Fortunately conditions were dry and no accident occurred. Cruise control was not engaged at the time as terrain was very hilly and twisting. Truck shifted and accelerated without warning. Continued trip without further problems.