- 6.2 engine lost propulsion & warninng light on dash flashed about 3-5 times. After that the trucks engine completely malfunctioned. When this happened i was traveling at 70mhp on interstate I-69 when the the truck lost power to the engine, steering and power braking. The truck was inspected by a GM dealer and they found the engine had blown & with that it caused damage to the coolant system & to the catalytic converterin which all was replaced at full customer cost. Prior to the engine failure 2 other times it lost power and had a rough ilde and trouble starting. 1st time the dealer could not replacate the issue the next time found a camshaft postioning sensor was bad which was placed at customer cost.

- Hanson, KY, USA

Since I bought the truck, it has had transmission problems. The truck will violently jerk forward between Park - 1st - 2nd gears (up and down) pretty frequently. The dealership denied being able to recreate the issue and nothing was wrong. After dropping the vehicle off a few times, the dealer service dept said they recreated the problem and replace the torque converter. It did not work and the service dept manager told me that they knew about the problem the whole time but were instructed by General Motors to not attempt to fix the issue. I called GM Company and a supervisor eventually admitted to knowing of the transmission and engine issues all along but the GM engineers have not found a solution yet but they are working very hard to figure it out. Since those calls, my lemon law claim with BBB Auto was approved, but suddenly denied with no explanation. Following that, the #2 lifter failed and damaged the cam shaft. All were replaced and that was at 70,000 miles. The transmission has not been fixed.

- Metairie , LA, USA

I-??m contacting you regarding my 2019 GMC Sierra 1500 with the 5.3L V8 engine. The vehicle is currently experiencing a cylinder 8 misfire (code P0308), accompanied by engine backfiring, ticking noise, and exhaust fumes inside the cabin. Additionally, the ESC (Electronic Stability Control) warning light is on, and performance is noticeably affected. To date, I have: -??Replaced all spark plugs and fuel injectors -??Verified proper ignition coil function -??Had an oil change on September 23, 2024, during which I reported early concerns about engine performance (shortly after the powertrain warranty expired) -??Had a transmission flush on March 17, 2025, in an attempt to resolve continued drivability issues Despite these efforts, the issue persists. Given the known issues with AFM lifters and camshaft wear on this engine, I suspect a mechanical failure related to that system.

- Mcminnville, OR, USA

While driving My 2019 GMC Sierra I heard a loud Bang And lots of Misfires. The vehicle immediately slowed on its own causing me to pull off the road and endanger myself and traffic around me. Engine light came on and the traction control light was flashing. The Vehicle was brought to Dealer where they Diagnosed the problem all lifter rods were frozen and the cam shaft was cracked. The Dealer has the affected parts.The vehicle was in the repair shop for over two weeks and close to $7,000 in repairs.

- Bayville, NY, USA

Cylinder 5 failure and cam shaft miles 78k. Have to replace full top end or brand new motor cost $10k up to $13k to fix at dealer

- Fort Atkinson, WI, USA

Complete engine failure. Absolutely insane. All lights on dash, engine seized while driving!!!!!!!!!!!!!! Unbelievable that GMC keeps making us fix issues and pay for it! They won't cover the cost. This has been happening too much and putting my family at risk!

- Bradenton, FL, USA

On [XXX] at approximately 2 pm the 2019 GMC Sierra 1500 AT4 (with 6.2 gas motor) motor died while I was driving in traffic. Incident #1 - The vehicle started sputtering and died - no alerts on dash until after the truck died - an empty fuel tank symbol briefly lit up on dash that led me to suspect a fuel pump issue as the fuel tank was full. Safety issue = vehicle failure with no warning in traffic putting occupants in risk. The vehicle would not start and was towed to the GMC dealer where I had purchased the vehicle. Incident #2, the 2019 GMC Sierra 1500 AT4 has an electronic gear shifter and will not go into neutral unless engine is running - problem as needed tow as not able to crank yet struggled to get towed as transmission will not go into neutral - apparently dealer has special tool to put 2019 GMC Sierra into neutral that is not available to consumer. Service department at dealer - Childre GMC in Milledgeville GA - contacted me on September 25, 2024 and stated 2019 GMC Sierra 1500 AT4 needs a Fuel Pump Control Module part number 13565641 but the part is not available in the GM system and may take weeks or months for part to arrive. Apparently, there are other GM trucks at this dealership waiting same part (appears to be a national issue not just a one time issue). Dealer gave me a GMC customer service number to call. I called GMC customer service on September 25, 2024 and registered a complaint that no parts are available to fix my car. Neither the selling dealer or GM customer service offered any relief with a loaner or rental car. Internet searches on forums focused on new GMC/Chevrolet trucks confirm that multiple consumers have this issue with the Fuel Pump Control Module and that GM cannot supply the repair part. The part is not available on the secondary supply chain like AutoZone, Oreilly, or similar. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Gordon, GA, USA

Check Engine Light came on while driving system scan states misfire cylinder 6 but resulted in the lifter being damaged as well as the cam shaft on a vehicle that has 108,000 miles. Prior to this I reported multiple times that it seemed that the transmission would slip and stuttered when on a incline and put in reverse. I was told it was a computer program issue and was charged for a software update which obviously did not fix the issue but ruined the engine.

- Harrisburg, NC, USA

I am a heavy highway construction inspector for wvdoh and while working on I 81 sb in martinsburg, wv this morning around 2:00 am while performing my duties I attempted to pull out of my lane closure into traffic when my truck literally got stuck halfway out into live traffic. It was as if I was stomping on the brakes instead of giving it gas. Fortunately I reacted swiftly and put the truck in reverse to back into my lane closure preventing a collision with a tractor trailer traveling at speeds in excess of 55 mph. I was literally shaking when I realized how close of a call it actually was and that not only could I or the truck driver have been killed, but so could the workers on my job have been injured and/or killed. I had to have my truck towed back to my field office. For some reason the truck started driving properly again. There is definitely something wrong and it is extremely fortunate that no injuries occurred on my project. I did notice a post on this website explaining the very thing that happened to me this morning. This issue must be addressed immediately before people are killed. Thank you, [xxx] information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6).

- Little Orleans, MD, USA