Purchased a used 2011 Chevy Avalanche with 87,000 miles one owner from a small dealership. After having the vehicle for about a week noticed it shuddering when pulling any kind of grade. Thinking it was some kind of misfire had all the plugs changed only to find that it also had an oil file problem with 1 of the cylinders. When the vehicle would shudder it was around 1500-2000 rpms. If I would give it more gas it made it past the 2,000 rpms and would shift with no problems. Needless to say the transmission is now toast as it gave out completely and needs replaced. No warning lights of any kind made me aware of a potentially serious problem. After reading more I am seeing that the transmission is something that GM has not fully taken care of as stated with older models. The transmission failed while driving on a major interstate roadway while nearing the top of a hill. It just went completely into neutral and would just rev the engine. The truck was carrying 3 adults and 2 children in car seats when this occurred. Thankfully we were able to get to the shoulder of the road safely. Currently the truck has 89,995 miles on it. I only put approximately 2000 miles on it since purchase.

- Mars, PA, USA

Engine runs rough at idle when engine light, service stabilitrak light and traction control off lights all come on. Upon acceleration, only engine light remains on. Will repeat at lower idle.

- Adrian, MI, USA

The contact owns a 2011 Chevrolet Avalanche. While changing gears to the drive position, the gears locked up and failed to move. The contact stated they experienced the same failure listed in NHTSA campaign number: 11V007000 (suspension), but the VIN was not included in the recall. The vehicle was towed to the dealer where it was diagnosed that the rear axle cross pin needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 100,000. The VIN was not available.

- Asheville, NC, USA

At times when the vehicle is slowing down/down shifting (more common when going up a grade) it will suddenly lunge forward (before coming to a stop) even with your foot on the brake. It seems to happen when downshifting from 2nd to 1st gear and sometimes it catches me off guard. This is a very dangerous situation especially when slowing down near people. I am always concerned that the vehicle is going to lunge forward and hit something or even worse someone. I hope NHTSA investigates this situation as other people have reported the same problem.

- North Providence, RI, USA

I was driving my truck at about 45 mph when the traction control light came on the dash and my truck suddenly went from 45mph to 20 mph and the motor began to miss fire and buck. If there would have been someone following me they would of hit me in the rearend due to the sudden slowing of my vehicle.

- Landisville, PA, USA

At times while slowing down (close to a stop) the truck will lunge forward unexpectedly pushes the truck forward. This is generally in stop and go traffic. It become very unsafe while the proximity of other cars during this time is very close and could cause injury. This is an intermittent problem.

- Parker , CO, USA

When slowing down the vehicle surges forward even when brake is being applied. It does not appear to be related to engine surge as it does with sudden gear change as if the vehicle is speeding up from a stand still. This occurred as I was turning into a parking space which caused the vehicle to veer uncontrollably to the right (was making a left hand turn into parking space) and hit a brick column. It has also happened when coming to a stop and persons were about to walk across road scaring them and me! the vehicle continues to experience these same issues. Dealership has not been able to fix though they did acknowledge that my vehicle was the only one experiencing this issue.

- Gulfport, MS, USA

I was in line at a drive through at burger king and as I pulled up to the cashiers window to pay for my food the engine started to accelerate. I put my foot on the brakes as hard as I could while the truck was shaking and lurching trying to go forward. I can't say for sure how high the tachometer was, but it seemed to almost peg for a few seconds while this was going on. Finally I jammed the transmission into neutral and the engine returned to normal idle. I say jammed because it took great strength to get it out of drive. For about 10-15 seconds this truck was totally out of my control. I drove away and parked for a few minutes to gather myself as I was visibly shaken..I was thankful that no one was in front of me in at burger king or that I was not in a parking lot somewhere where someone could have been injured or killed. I had brought this vehicle in more than once to the dealer (rk Chevrolet) and complained about the transmission not shifting properly and was always told they could not find a problem. After reporting this they decided to put a device to monitor the computer. I drove around with this for about 3 months and nothing happened and they said the data collected was inconclusive. Since the truck had just went out of warranty they said they could not do anymore. This is totally unacceptable.

- Virginia Beach, VA, USA

I own a 2011 Chevrolet Avalanche ltz and at times when the truck down shifts it will lunge forward. I really need to have my foot firmly pressed on the brake to keep the truck from possibly hitting something or someone in front of me. It does not do it all the time and it's rather random. I feel that is worse then it happening all the time because I don't know when to expect it. I have not received any notification of a recall, but I feel a fix is definitely in order. Something is not right and it could result in a crash.

- North Providence, RI, USA

I have began to notice when slowing down (foot off the gas and coasting with foot on brake, or brake applied) at any area where my speed decreases to less than 15 mph that my Avalanche will seem to sort of lunge forward. The first time I experienced this I believed it was related to me and ignored it. The next couple of times I experienced this I thought there may be something wrong with the gas or engine. I have spoken with several other owners (who own the same year model Avalanche and Suburban - the Suburban and Avalanche are made from the same frame/body/parts) and they state experiencing the same issue. I must be cautious to ride my brakes and be read to heavily apply them now when taking an off/on ramp and vehicles are in front of me as my vehicle has lunged forward before with vehicles in front of me. I noticed here that (at the time of this submission) that two other users have reported the same incident. I am hoping that my report here will help open an investigation with Chevrolet on this issue.

- Benton, AR, USA

At times when my Avalanche is slowing down (close to a stop) the truck will lunge forward. It feels like it's something with the transmission (downshifting?). almost like a surge of energy unexpectedly pushes the truck forward. It does catch me off guard at times, but luckily I have not struck anything when it has happened. It does not do it all the time, but rather intermittently. I am hoping that GM can figure out why this is happening and possibly issue a recall to fix the problem.

- North Providence, RI, USA

When I am slowing down to a stop the transmission will suddenly make the vehicle surge forward quickly. If I not just as quick to apply a firm brake I risk hitting the car or pedestrians near me which has happen on several occasion. On one occasion, as I was turning into a parking space the vehicle suddenly surged forward so forcefully that it cause the front left bumble to travel outside the planned path and hit a brick column. This problem only occurs in situations when I am slowing down, I.e. making turns, traffic lights, parking, etc. It can be frightening when it occurs unexpectedly. Recently took into local Chevrolet dealer. They acknowledged the problem and said Chevrolet engineers are working on a fix where the transmission's computer is altered. But they didn't seem confident in the outcome.

- Gulfport, MS, USA