GMC Complaints

L87 engine already replaced under recall. Failed with same issue in the middle of the road after making heavy squeaking noise.

Was taken in for recall at 74,000 they put on a new oil fill cap, did oil change and had catastrophic engine failure at 77,000 miles. Engine replaced by dealership.

My truck has the same issues for the transmission and engine problems I have taken it to 4 dealerships and they all say the same thing. The first one I spent about 3 hours there and they changed the 20 oil to the 40 oil and said that will fix the issues but it hasn't i called GMC to report this and they sent me to the others but they said it's been looked at and I know one of them didn't do anything to see the issue.Gmc called the other day and I told them I will let the engine locked up or the transmission keep doing the same thing and they'll have to fix the issue then.I do have 109000 miles on it but thus issue has been going on for 4 years they said I have 150000 miles for the issue but I do t think that is right.I paid them cash money for the truck when I bought it

Issues with the google voice, transmission issues, engine failure to start or restart. Reported same year vehicle was bought. Repeatedly. Dealership even with video evidence stated could not repeat issue and nothing wrong. My car then starts rattling in the engine and they do a full replacement had it for over three months. Now it’s leaking fluid and smoking. They try to send the consumer away and delay delay until the warranty is over. Unethical practices. They knew there was an issue with my engine as it was on the recall list but kept denying any issues until complete failure. Now less than 20 days after that repair the car is leaking and smoking.

When starting to accelerate from a red light. The car in front of us was accelerating faster. Yet our car initiated an emergency braking action at around 15 MPH. It was very jarring and I still have a headache more yhan 1 hour after the incident.

Took ownership of this vehicle on XXX. 6.2 motor build date XXX at Tonawanda plant. Currently have 10,600 miles on vehicle. First and second oil changes at GMC facility T&T Coast Buick, GMC located in [XXX] First at 4,441 miles, oil part number 19420077. Second oil change at 8,379 miles, oil part number 19420077 This oil part number is for 5W-30. ACDelco bulk engine oil (Dexos1 Gen2 Full Synthetic 5W-30). The correct oil was not used. From what I have read this is a GM "oil trap" so if there is a problem with the motor GM can deny warranty coverage because the wrong oil was used. I have not adressed this with the dealership yet. If there is a 6.2 motor problem with my vehicle in the future am I going to be denied coverage? I am worried. I also have the extended warranty. Thank you. [XXX] [XXX] [XXX] [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

I bought this truck from a dealer at the end of july 2026 and it only had 27k miles on it. I got the carfax and saw all the times of service and checked that this truck was inspected and went to the new oil type, filter and cap. It also was showing it had the special warranty due to recall. So i assumed everything was good to go and the truck was relaicle. Not even 18 days later and less than 800 miles I broke down mid drive. I was traveling at 45 mph and lost all power and almost caused an accident trying to get over and parked safely. There was no warning light or indication of it breaking down or having a mechanical issue. It went to the dealer and they diagnosed it as complete engine failure due the issue GM is having currently. They did order a new motor and it took two weeks to get in but they are in the process of the engine swap as we speak. I am sure i will get more details this week....but I am concerned now amd honestly wish I wouldnt have bought this truck considering I am seeing reports of new motor swaps having catastrophic engine failure two or three times. So at this point im in limbo waiting for the new install and hopefully it doesnt fail again

Truck died while driving on a major highway due to a faulty fuel pump module. The vehicle was blocking an intersection. The vehicle could not be put into neutral without the engine running because of the electronic transmission. Could not move the vehicle out of the intersection and out of traffic. I found out later that to put the truck in neutral requires a special tool, and going under the truck to engage the bypass, which is very difficult and unsafe on a major roadway.

We were told when we purchased our 2026 GMC Sierra 1500 that all the engine problems have been remedied. Purchased our new truck January 3, 2026 put 2001 miles on the truck went on June 29. The engine suddenly just stopped while driving on the highway. We were able to pull over unable to ever get it to start forced to have it towed to a nearby GMC dealer where it has been ever since were told it had to have a complete new engine put in we have corresponded with General motors on three different occasions we still sit with no offer as we did apply for a lemon law buyback but General Motors continues to sell these vehicles which is very deceptive and misleading as this situation was not remedied in any 25 or 26 models.

The Engine made a noise and it seems to me that this engine will loose power and leave me in a situation that could cause an accident or breakdown in the middle of a bad situation. I don't trust this truck and its engine and i refuse to drive it now.