GMC Complaints

Driving on highway, engine light came on with many warning lights. Was just starting on a trip to SC then OH to help father for a surgery. Lifters went bad within fist 5-6k miles on the truck (6.2L) causing other damage to the engine such as bent rods (etc). Dealer repaired all DFM Lifters as there were failures on both sides of the engine, but it still sounds like there are issues internally. It is a 2020 manufactured in 2019, I have not had additional mechanical issues, but I have purposely not driven it as much since I feel that it is not dependable. It currently only has about 27k miles and sounds worse than my 2007 Lexus engine with 180k+ miles. I wanted to fill this out, so you have the data for the engineering investigation.

When I put the car in park and shut off the vehicle, I am getting a shift to park message with an audible sound. The car is in park already. Happens every time almost. It’s not showing up as a recall under my vin. Just got the car. I have seen more recall issues on Google and am concerned those will also occur which are more serious and aren’t listed either.

Engine failure with the 6.2 engine. My engine failed the Pico test in July of 2025 with 66k miles. The entire engine was replaced and I was told this would “fix” the engine issue. On April 25, 2026, my engine failed while I was driving at highway speeds. The engine was knocking and I pulled over as I could not accelerate it. I had it towed and was told by the dealership that the rod bearings failed and I would need an entire new engine. 9 months and 10k miles after a brand new engine was installed. This will be the third engine in this vehicle since I’ve owned it. GM’s “fix” for the 6.2 recall is not a fix. It’s pushing the problem down the road, risking lives by putting people in vehicles with known engine failures and no true fix.

IOK Radio Module failure. Inhibits hands free calling, total loss of all audio including safety chimes, dropped emergency call capability, multiple software updates have failed to resolve it. Vehicle is still under warranty.

IOK Radio Module failing. Would happen 10 times in less than 5 miles. Vehicle has been seen 3 times before diagnosing as IOK Radio Module failure. Inhibits hands free calling, total loss of all audio including safety chimes, dropped emergency call capability, multiple software updates have failed to resolve it. Vehicle is still under warranty. Serviced at Garrett Motors in Coolidge, AZ

The contact owns a 2019 GMC Sierra 1500. The contact stated that while driving approximately 65-70 MPH, the engine seized and made an abnormal sound, nearly causing a semi-truck to jackknife and crash into the vehicle. There was no warning light illuminated. The contact was left stranded in the west desert of Utah, where a wildfire had started, and the contact did not have phone service. Additionally, the vehicle stopped on a two-lane road with heavy semi-truck traffic, leaving the contact frightened and terrified for her safety. The contact jumped out of the vehicle. Migrants who were tending the sheep nearby assisted the contact in pushing the vehicle to the side of the road. The vehicle was towed to the dealer, where it was diagnosed with engine failure, and the dealer determined that the engine needed to be replaced. The vehicle was not repaired. The contact related the failure to NHTSA Action Number: EA25007 (ENGINE, ENGINE AND ENGINE COOLING). The manufacturer was notified of the failure, and the contact was misinformed that the model year was not included in the NHTSA investigation. The contact informed the manufacturer that she no longer felt safe driving the vehicle, regardless of the engine replacement, and the contact advised the manufacturer to guarantee that the failure would not recur after the engine replacement. The manufacturer then referred the contact to the NHTSA Hotline for assistance in investigating the safety issue. The vehicle was not repaired. The failure mileage was 122,187.

The contact owns a 2023 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed on several occasions, the pedestrian warning alert unexpectedly illuminated. The contact stated that during the failure, the braking system became inoperable and then the brakes locked up, causing the contact and a passenger to suffer whiplash. The contact stated that there were no pedestrians near the vehicle when the failure had occurred. Additionally, the contact stated that while attempting to reverse, the pedestrian detection system failed to display a warning when a pedestrian was near the vehicle, almost causing the vehicle to strike the pedestrian. The vehicle was taken to the dealer, where the contact was informed that the failure was related to an electrical anomaly and a hardware failure. The contact was advised that an over-the-air update might be issued to address the issue. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 12,000.

Hello, I was driving on the highway with my family and my engine had a sudden loss of power. I only have 52,000 miles on the engine and it has been serviced the entire time. We almost got in a major accident as we had cars and trucks moving around us at a very high speed as we tried to pull over in the breakdown lane. I brought the car to Daddario GMC in Shelton, CT. They did a diagnostic test and said that cylinder 2 was misfiring. Upon closer inspection they saw that there was oil sitting on top of the piston head which indicates engine failure. I have since contacted GM warranty services given my car was just past the warranty date of November 2025, but still under the 60,000 miles of coverage. I did some research and have seen this is a very common with these engines as GM did a recall on 600,000 already. For some reason my VIN # is not listed on the current recall even though my engine is in the same year as the others that were. I would like GM to cover my engine 100% but was told they may only pay a % to fix it. Can you do anything to help me get them to cover the engine at 100%? I also wanted to let you know about this issue as my VIN was not under recall and this may happen to other people/families who have the same engine as mine that isn't recalled. Thank you, [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

On 3/14/26, on I-75 in Troy, Michigan at 70mph the vehicle, with 4000k miles on the odometer completely shut off. I pushed to restart the engine and it would not restart. My whole family was in the car and we were on a curve. I was able to coast to a flat shoulder. The vehicle would not restart or shift out of park. OnStar took seven hours to tow the vehicle. The dealer is installing a new L87 6.2L engine. I do not have the vehicle back yet. I received an economy car as a loaner. The dealer says GM will not extend the factory warranty despite the engine replacement. My family could have been easily killed.

Got in started Truck and there is no Sound anywhere... none for blinkers, radio, warning lights if there to be any. ZERO sounds. This has been investigated by Hertrich Service--showed video of no sounds coming from truck speakers at all. This is safety hazard with no audio warnings or blinkers, flasher sounds at all.