2021 GMC SIERRA 1500 Complaints

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at various speeds up an incline, the vehicle was vibrating and shuddering. The failure persisted over time. There were no warning lights illuminated. The vehicle was taken to the local dealer, but the vehicle was not diagnosed or repaired. The vehicle was taken to a transmission shop, and it was determined that the transmission needed to be replaced. The manufacturer was not contacted. The approximate failure mileage was 68,000.

While driving on the highway the engine 6.2 GM seized suddenly at high speed. The truck shut off completely and left rolling without any control. I had work my way accross lanes to the breakdown lane. While doing so I was almost hit by an 18 wheel trailer truck, who luckily was able to change lanes to avoid hitting me. The reason I was almost hit was because of my low speed since I had now power or acceleration.

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at various speeds and depressing the accelerator pedal, the vehicle hesitated to respond and shuddered. The vehicle was taken to the dealer, where the fuel tank was cleaned, and the contact added fuel treatment to the fuel, as recommended by the dealer; however, the failure recurred. The contact stated that while driving from a complete stop, uphill, and while driving 50 MPH, the vehicle shuddered and experienced erratic transmission shifting. The check engine warning light was illuminated. The vehicle was taken to Dixie Buick GMC (14565 S Tamiami Trl, Fort Myers, FL 33912); where it was determined that the vehicle was experiencing a abnormal shudder. The dealer replaced the transmission fluid; however, the failure persisted. The contact stated that the failure had become progressively worse and mostly occurred at 1,200 RPM. The dealer was contacted, and an appointment was scheduled for diagnostic testing. The vehicle was not diagnosed or repaired. The contact related the failure to NHTSA Campaign Number: 24V797000 (Power Train); however, the VIN was not included. The manufacturer was notified of the failure. The failure mileage was approximately 8,000.

I purchased a new 2021 GMC Sierra Denali with a 6.2L engine on 03/05/2022. On November 10, 2022, I started the truck, and the engine seized up. The truck had 9018 miles on it and 274 engine hours. The main bearings and possibly the connecting rods bearings was the problem. On January 27, 2023, I finally got a new engine installed in my truck. I had to pay for the repairs.

Driver side lifters collapsed and push rods failed on freeway without warning at 12900 miles on truck.

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at an undisclosed speed, there was an abnormal clunking sound coming from the rear suspension. The check engine warning light was illuminated. The vehicle was taken to the dealer, who diagnosed a failure with the rear suspension. The vehicle was repaired, but the failure reoccurred 4,000 miles later. The contact stated that while reversing, the contact heard an abnormal clunking sound coming from the rear suspension. The contact also stated that there was also a strong antifreeze odor permeating the interior of the vehicle. The vehicle was taken back to the dealer, but not yet diagnosed. The vehicle was not repaired. The manufacturer was notified of the failure, and a case was opened. The failure mileage was 38,000.

On the morning of 1/19/25, my 2021 GMC Sierra 6.2L AT4 went into limp mode heading south on HWY 207 in Leavenworth, WA at approximately 60 m.p.h. Fortunately, I was able to avoid a rear end collision. I quickly turned the truck off in the middle of the road and restarted it with a CEL. When I returned home almost 180 miles away, my local mechanic diagnosed a code P0303 and cleared it. Since, the truck has continued to shutter at various speeds without throwing a code. It is currently at Haselwood GMC in Bremerton, WA being scanned, recorded, and findings set to GM waiting for resolve. I have notes, exact dates, times, call records, return voice mail messages, and dealership personnel spoken to, etc. The dealer’s lead technician and I were able to replicate the shutter on a road test together on 1/27/25 at 3 p.m. after having driven just 10 miles. During my visit on the morning of 1/30/25, the lead technician stated he has since been able to replicate the shutter seemingly getting worse. I was strongly encouraged by the service manager, service writer, and lead technician their collective “personal recommendation” was to not take the truck back. Haselwood has had the truck since 1/27/25. Still awaiting a response and resolution.

lifters in the left and right side snapped into 3 pieces. Caused engine failure happened 2 different times. All before 50,000 miles. The first time was before 30,000 miles.

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 24V797000 (Power Train); however, the contact believed that the remedy offered would cripple the vehicle and interfere with his work. The contact works in Alaska and the remedy involved the transmission being limited to fifth gear, preventing the possibility of a wheel lock up condition, which could occur while downshifting from eighth gear. The manufacturer was made aware of the issue and advised the contact to find a dealer that could repair the transmission. The contact had not experienced a failure. Parts distribution disconnect.

The engine locked up with no warning I called the dealership and they said it was out of warranty as it has 77000 miles. upon further investigation I found that the front main bearing on the engine had gone bad and caused the engine to lock up. GMC refused to accept any responsibility for the failure.