Exhaust fluid quality poor appeared on the dash display, so I toped it off with more fresh def and the warning went away.3 days later the same warning came back on the dash display only with a new warning with it that said vehicle speed will be limited to 55mph next fuel fill, it did! I took the truck to the dealer they found bad nox sensors 1&2.repairs where not done because I felt that should be some sort of recall on defective parts that controls the drivability of a vehicle. On Feb-4-2015 I received a letter from GM after 2 years telling me that my truck may have nox sensors that can become contaminated and that GM is extending the warranty on the nox sensors and the wire connectors for 10/yrs. 120.000 miles which ever comes first. So I go back to the dealer and show them the letter from GM and show them my receipt from when I came in 2 years ago that shows that the nox sensors were defective way back in 2013 and are still on the vehicle and I need the repairs done per the letter from GM. The dealer is refusing to repair the vehicle because of the mileage that is now on the vehicle, however the defective parts that failed when the vehicle was within the mileage are still on the vehicle and I feel should be replaced and repaired or reimbursement for $800 programmer. I have contacted Chevrolet and they are working with that dealership to try and resolve this issue. Case number is available if needed, GM letter number is 13386.

- Beaumont, TX, USA

Driving about 60 mph about 10 miles into the trip when the truck lost speed, the ABS brakes did a slight on and off pulsating every couple of seconds, the engine was running rough and giving it gas the engine revved up but wouldn't go anywhere. Speed dropped down to 35 or 40 mph and wouldn't go any faster. The dash indicator showed messages stating stabilitrak traction control turned off and check engine light is on. It jolted real hard when it shifts gears. When I mashed the brake it didn't want to come to a complete stop without pressing the brakes to hold the truck there. I pulled into a store popped the hood and finding nothing I turned the truck off for a few seconds and restarted it but nothing changed and the error messages were still being displayed. The trucks engine was running rough. I headed home and it didn't have any power and jolted hard as it shifted gears. I coudln't go but 35 or 40 mph on the level ground. If I went up a slight hill the truck slowed down more until I got past the hill. I gave it gas and the engine would rev up but had no power and wouldn't go 35 or 40 mph. I parked the truck in the garage and in 10 minutes I went to start it to get the error messages and it started up fine and the engine wasn't running rough. I drove it 1/2 mile down the road and back and it ran perfect. I googled the error messages and found alot of complaints and comments about this issue on the Chevrolet forum website. No recall information just alot of people experiencing the same issue and alot worse cases that almost caused accidents. Is there a recall on this issue? I read that I will probably have the issue again because after it sits for 10 min it probably won't have a problem until a few minutes or days later. I can only hope doesn't cause me to have a wreck and kill myself or someone else. This is a major issue and should be recalled to fix the problem.

- Denton, TX, USA

2011 Chevrolet Silverado. Consumer writes in regards to the vehicle throttle position sensor recall notice. The letter advised consumers not to take their vehicle to dealer, unless they experienced the problem. The consumer was concerned he may experience reduced engine power, while driving at night.

- Livonia, MI, USA

The contact owns a 2011 Chevrolet Silverado. The contact stated that the vehicle failed to respond to acceleration attempts. After continually depressing the accelerator pedal, the vehicle suddenly jerked forward. Additionally, the contact noticed the vehicle hesitated when accelerating. The vehicle was taken to the dealer for diagnostic testing. The technician was unable to diagnose the failure. The vehicle was not repaired. The approximate failure mileage was 22,000.

- Vancleave, MS, USA

#1. vehicle accelerates when letting off gas, even while going uphill the vehicle will accelerate. You can go up a steep hill without touching the gas. Brought the vehicle to the dealership they replaced, the throttle body, gas pedal assembly. They reinstalled the original parts and told us that this was normal. We drove other 2011 Chevy Silverado's which did not do the same thing. The dealership told us that all the 2011 Chevy Silverado's accelerate on their own. #2. there is a clunking noise from the rear when driving over bumps. The dealership said this is normal backlash, and did not do anything.

- South Grafton, MA, USA