With out any warning the truck stop running at stoplight an would not start back up. We could not move the truck out of the road and blocked traffic for almost 1 hour waiting for the tow truck and getting it loaded on the tow truck (truck would not go in to neutral). The truck is now at the Dealer and they are saying that the engine seized up and will need replaced.

- Gilbert, AZ, USA

On Saturday March 1st I was driving East on I-10 in Florida when my trucks engine lost power. I managed to get over onto the shoulder of the road and got out of the flow of traffic. Very scared I was going to get hit before I could get off the interstate. Motor was making a terrible noise like the lifters let go. I was beside the interstate for about 3 hours trying to find a tow truck to come get me and the truck off the side of the interstate. I had the truck towed for about 60 mile to get it back home to the dealership. The truck has 26,000 miles on it and the dealership told me the motor was no good and that there is metal pieces in the oil pan. 2 weeks have past by and they can't tell me when they will receive a replacement motor. What am I supposed to do? $80,000 truck 2 years old and the motor is no good. Thanks

- Thomasville, GA, USA

I own a 2023 GMC Sierra 1500 Denali Ultimate. The truck had about 19k miles on it when the engine seized while driving on the highway late at night in January. This was extremely dangerous as I was going 55mph over a bridge and lost the engine. I was stranded on an exit ramp unable to move. It was cold that week so it was 5 degrees. Onstar informed me that since the truck could not be shifted into Neutral that it would need dollies and a flat bed. They said they could get to me at 8am which was 9 hours from when the truck broke down. It was 5 degrees out and I had no heat sitting on the highway. I ended up calling a local tow company and they were able to get to me but I had to wait 3 hours. The truck was towed to the deal and they confirmed that the engine seized (it is a known problem) and it needs a new motor. They said there is a big back log of engines because many have this issue. I still have not provided a timeline for the truck to be repaired.

- Upper Makefield, PA, USA

During travel of the highway, the motor suddenly lost power and shut down with no warning lights or symptoms prior. Although I was able to get to the side of the road, the electronic shifter does NOT allow the vehicle to be put into Neutral. This is a known GM issue. This morning the dealer confirmed the engine needs replacement.

- Wentzville, MO, USA

I left my house & was driving my truck down the highway for about 2.5 miles. All of a sudden the engine locked up & the battery went dead. I barely coasted off the opposite side of the road where the closest side road is & a semi pasted shortly after. I felt very lucky my truck made it off on the side road instead being run over by the semi truck. I then had to call a weaker & have it towed to the local dealership that services GMC trucks. After 4 days I finally got the worst news, the truck needs a new 6.2 engine. My 2023 GMC Sierra AT4 with 38k miles had an engine that locked up & I was flabbergasted. I started searching this issue on the internet & couldn-??t believe how common this is & nothing has been done about this. I would assume a recall from GM would be appropriate considering the sheer number of 6.2 liters engines having issues over & over. This is absolutely unacceptable. I could have been seriously injured or even worse killed by the negligence of GM on this issue. I get it, GM made a mistake with this 6.2 engine and it-??s going to cost a lot of money but my research tells me this appears to have been happening for a few years. As I sit here today my truck is sitting in a dealer lot with a busted engine & a new one is on backorder. I am currently driving a dealer -??loaner-?? Chevy trailerblazer. It could be weeks or months before I finally get word on another 6.2 engine replacement from GM. I own a small farm and do not have a truck to haul hay or feed for horses. Can the National highway administration please help me" I thought I was buying a dependable 2023 GMC sierra 1500 AT4 & instead bought a lemon. Apparently hundreds of thousands of other 6.2 liter engines like mine are a HUGE safety hazard & should be recalled. This seems like an open & shut case & after reading into the matter I can-??t believe Gov. organizations like the National Highway safety administration has not did more and let GMs 6.2 liter engine contine on. What-??s left to investigate"

- Gravette, AR, USA

purchased a 2023 GMC Denali, 1500 on January 12, 2025. after about a week, Started to hear knocking ticking noises took the truck to the dealership with 20,362 miles. dealership diagnosed that the lifters on the driver side went bad dealership replace driver side bank, picked up my truck drove it a little over 500 miles and still heard knocking ticking noises. Send it back to the dealership and dropped it off dealership told me they would keep me an update on it.Emailed called have absolutely no idea what-??s going on with my truck. The dealership did mention of a possible engine replacement. But did not confirm after many attempts. Trying to attempt to contact the dealership emails phone calls still no answer. Called General Motors. They informed me the dealership ordered a new engine for replacement. That definitely worried me and I asked for a vehicle replacement or refund General motors, declined my request. Now I am not so confident in my truck what else could go wrong since the engine is going to be replaced" What about the transmission? Could it affect it" I don-??t know> The damage was significant in order for the engine to be replaced you just don-??t replace an engine just because, there was no light indications that something was going wrong with my truck. I-??m glad I wasn-??t driving far when I was hearing these noises coming from the engine because the engine could have seized left me stranded who knows could have crashed if the engine came to abrupt stop because of the engine failure. I purchased this truck January 12, 2025. The total of time that I have had my truck since January 12 has been 15 days. today is February 6 on Friday, February 7. My truck has been in the shop literally 30 days exactly. Still no update on when it will be ready. This is so frustrating and such a big inconvenience.

- Santa Barbara , CA, USA

On the highway, the engine suddenly stopped working. Everything turned black. While driving, the screen turned back on but the motor did not start again. I pressed the breaks and the start button to turn the engine back on, while still driving on the highway. It turned back on but then stopped again before I had time to pull to the side of the road. I did the same again and got to bring the car to the side of the highway. It started and stopped several times. I got it to run again so I exited the highway. It turned off again once I was off the highway. I got to drive it slowly to the dealer. He said it had never happened (which is untrue, I found out it is a recurring problem on the GM 6.2 liter). I had brought the car for service to the same dealership about a week prior to the incident. At that time, I told the dealer that the motor was making subtle weird noises. They serviced the car and gave it back to me stating that everything was ok and that nothing showed on their computer. When I picked up the car after the shutting off incident, I was told that their system showed prior issues but that nothing needed to be done since it was not detecting any problem at the time of pick up. About a week after I picked up my truck (after the shutting off issue was supposed to have been taken care of), I returned because I was still noticing the noise. While on a test drive with a GM mechanic, the motor suddenly started making very loud clicking and squeaking noises. He told me to stop right away. The manager at the dealership told me I would get a new motor because there was a recuring issue with the GM 6.2l. After a week, he said only some parts would be changed and that GM would not replace the whole motor. I told him I did not feel safe driving the truck and he said GM decides what to replace not me. I read online that the motor and all oil filters, ducts etc need to be replaced to avoid debris and future problems. No warning light ever went on. Terrifying experience.

- Boca Raton, FL, USA

i was driving on the highway and the truck just shut off and rear wheel locked up almost caused me to wreck the truck. got truck pulled to side of the road finally after steering got real tight and very hard to steer to side of road. truck would not even try to start and engine warning light popped up on dash. i had to get truck towed for $243 to turner gmc in new holland, the dealership said it was a known issue since they had 2 trucks in their shop with the 6.2 L engines getting replaced. this was a very scary moment for me and now i have nothing to drive out money from towing and dealer told me it could be a few months before i get truck back. now i will have to pay for a truck that dont run at all.

- Dover, PA, USA

At 9,100 miles my 2023 pickup truck experienced engine failure. It was inspected by dealership in the town where truck was purchased and it is determined that it will need a new engine due to "bearing failure". This occurred 2/24/25. No indicators or warning messages appeared.

- New Ulm, MN, USA

The contact owns a 2023 GMC Sierra 1500. The contact stated that while his wife was driving 60 MPH, the vehicle came to an abrupt stop, and the engine was seized. There were no warning lights illuminated. The driver was stranded on the highway for approximately two hours. The vehicle was towed to the local dealer, where it was diagnosed that the camshaft bearing had disintegrated. The vehicle was not repaired. The manufacturer was contacted and opened a case. The failure mileage was approximately 22,872.

- Cadet, MO, USA

I started truck and engine light came on.Coolant fan went super loud and would not stop at high speed. Code P1098 was seen.The dash read reduce acceleration drive with care.I had to have vehicle towed to GMC dealership.

- Fresno, CA, USA

The engine has blown for the 6.2L V8 Denali with 31,300 miles. I was told that this is happening on several of these engines. They told me it would be 3-4 months for repair as the engines are on backorder. I am not able to use a truck that I have purchased and am paying on.

- Salem, SC, USA

Driving on a road. Suddenly the engine shut off and would not turn back on. I was stuck in the middle of the road with out the ability to put the truck in neutral to push it out of the way.

- The Hills, TX, USA

I was driving on the interstate and the vehicle just shut off with a warning stating conditions not right to shift. I had to drift off the interstate and the vehicle would not restart. This happened on 12/4/24 and has been at the dealership since.

- Fairmont, WV, USA

Driving truck at highway speed and went to pass a group of slower vehicles on my right. I increased speed to 75 mph and the engine stopped and I had no acceleration. Engine would not shift into Neutral and would not restart. I coasted off to an exit ramp and the truck stopped in the middle of it blocking traffic for about an hour. Highway Patrol was on site to help direct traffic through the intersection of the off ramp and side road. We sat for approximately an hour before a tow truck could get us out of the intersection. The truck transmission was locked tight and the tow truck had to put the back wheel on skates to move it. I had to pay $175 to this tow truck company to move me approximately 200 yards to a local restaurant where we waited for the GMC provided tow service to arrive. GMC provided tow truck would only tow to nearest dealership which was in Weimer, TX. At the time of failure there was no warning. The truck just shut down making loud wining noises since the transmission was still in gear. This was an extremely stressful event and I was worried that someone was going to strike us at highway speed from the rear. Traffic was heavy that day on [XXX] heading [XXX] towards San Antonio and most left lane speeds were 75-80 mph and bumper to bumper traffic. The GMC Dealer in Weimer was very professional and inspected the engine on Dec 2nd notifying me that is was a total failure and would need to be replaced under warranty. The dealer had a new engine in hand within a few days and the truck was repaired with two weeks. I had a couple other issues with the OnStar system and the wireless after I picked up the truck and drive it home. I returned it to the dealer and proper parts were ordered to replace a bad control module that had failed during the engine failure. It took some additional time on my own after this was replaced to get my OnStar account back up and running correctly. This truck also had "tailgate drop" issues that the dealer fixed. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMAT

- Spring, TX, USA

I have a 2023 6.2L V8 GMC AT4. I have ~ 27,000 miles on the truck. On 2/1/2025, I was driving down the interstate going 78 mph and I lost all power to the truck. This was a MAJOR safety issue because I could only "coast" to a stop. I fortunately was able to get to the emergency lane and call a tow truck. I put others at risk because I had no choice but to move over. I had my truck towed to Brookfield Buick GMC dealership. Because I had no power, I had no HEAT. I sat for 1.5 hours before a tow truck could come to me. I was freezing because it was 20 degrees outside. The dealership told me that I had massive engine failure "seizure", which will require a NEW engine. I had no warning lamps or messages prior to the failure. This was a BIG safety issue and I'm fortunate I didn't get injured.

- Pewaukee, WI, USA

1) [XXX] - Was driving on the interstate at 65 - 70 mph when the truck suddenly shut off and shifted to neutral. I was in the far left lane and had to coast thru 2 lanes of high speed traffic to the right shoulder before the truck stopped coasting. Once I coasted to a stop on the right shoulder of the interstate, I tried to crank the truck up a couple of times and it finally cranked and I proceeded on to my destination. When I reached my destination and was attempting to park, the truck shut off again and would not crank after that. I then called roadside assistance to send a wrecker and take it to my local GMC dealer in Montgomery, Alabama. 2) My safety and others was put at risk when the truck, without warning, shut off and lost power while driving at 65-70 mph in heavy interstate traffic causing the truck to suddenly decrease speed and having to maneuver through traffic, without power, while coasting to the side of the road. 3) [XXX] - The service department at Mullinax GMC in Montgomery, Alabama called me about a week later to say the engine had "LOCKED UP" and that they had contacted GMC to begin the process of getting it fixed. They indicated that this was not uncommon with this model truck, and that it happens sometimes. 4) There were absolutely no warning lamps, messages, sounds or any other symptoms of the problem prior to the engine failure. I was caught completely off guard when the engine shut off. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Prattville, AL, USA

Complete engine failure while driving on interstate. Vehicle went into neutral. After rolling to a stop on highway. Vehicle would not go into gear. Tow was unable to put vehicle into saftey mode and had to drag vehicle onto tow bed. At dealership techs were also unable to get vehicle to turn on or go into gear. Dealer advised the engine was complete seized. This happened while traveling on the highway there was no warning or signs of something being wrong. Vehicle simply lost all power and went into neutral while traveling 70mph with 37k on the odometer.

- Bethlehem, PA, USA

I started my truck on [XXX] and after driving less than 3 miles the check engine light came on and then light for traction control needs service came on. I stopped and notice engine was idling weird. So I called dealer and they recommended I bring in. I proceeded to drive but could not drive over 40 mph as the engine would not idle past that and started hearing clicking noises. I slowly get the vehicle into service at McKinney GMC Buick in McKinney, TX. Two days later I get a call stating that engine needs to be replaced due to bearing failure and excessive metal in oil and oil filter. Which damaged the engine and is not repairable. The service center informed that this is common with my 6.2 L V8 and there are four other trucks same issues. The engine is on back order and don't know when I will be able to get my vehicle back. This appears to be a known issue for GMC and they are not telling people who could be in danger on road at any moment without warning. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Aubrey , TX, USA

Traveling on the interstate at highway speeds of 75mph and the engine spun a bearing resulting in complete engine failure.

- Brighton, CO, USA