2024 GMC Sierra 1500 Problems: Engine (344 Complaints)

I purchased a 2024 GMC Sierra 1500 Denali Ultimate equipped with the 6.2L V8 engine on XXX. The vehicle currently has approximately 25,000 miles. On XXX, the vehicle underwent the GM recall repair related to the 6.2L engine at Don Mealey Chevrolet. On XXX, approximately nine months after the recall repair, my family and I were traveling on the [XXX] with my two children inside the vehicle when the engine suddenly experienced a major failure. The vehicle became inoperable while we were traveling on the highway and had to be stopped and subsequently transported to Schumacher Buick GMC in [XXX]. The failure occurred unexpectedly while the vehicle was being operated normally. Having an engine failure while traveling on a major highway with my two children in the vehicle created a significant safety concern because of the potential for loss of power and the danger associated with becoming disabled in active highway traffic. GM has subsequently authorized replacement of the engine under warranty. The vehicle remains at the dealership awaiting completion of the engine replacement. I am reporting this failure because the vehicle had previously received the GM recall remedy for the 6.2L engine issue and subsequently experienced a major engine failure at only approximately 25,000 miles. The failure occurred approximately nine months after the recall repair. I am concerned that the previous recall remedy may not have adequately addressed the underlying condition associated with these 6.2L L87 engines. I am requesting that NHTSA document this failure as part of its investigation into 6.2L L87 engine failures and evaluate whether the existing recall remedy adequately addresses the safety-related engine failure condition. Vehicle information: * [XXX] GMC [XXX] 1500 Denali Ultimate * 6.2L V8 engine INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The vehicle was part of the GM L87 engine recall. The vehicle was taken to the dealership in late 2025 for recall service. The dealership inspected the vehicle for vibration and determined that it required an oil change and updated service manual to require 0W-40 oil. On June 21, 2026 the vehicle experienced an engine failure.

After the initial recall inspection was performed, I was informed that my vehicle was not affected. Subsequently, the vehicle experienced a catastrophic engine failure while traveling westbound on [XXX] near [XXX], approximately one mile from [XXX]. While traveling at highway speed, the vehicle suddenly began losing speed and power. I was positioned between two semi-trucks, creating an extremely dangerous situation. At first, I looked to see if I was traveling uphill because of the unexpected loss of speed. I then pressed the accelerator in an attempt to maintain highway speed. The vehicle abruptly downshifted and the engine RPM increased dramatically. Immediately afterward, warnings appeared on the instrument cluster, including “Engine Oil Temperature High” and instructions to pull over and allow the vehicle to cool down. The vehicle continued to lose power, creating a serious risk of collision due to the surrounding highway traffic. The vehicle was subsequently towed to Findlay GMC, where it was inspected and diagnosed with a failed engine. The engine was ultimately replaced. This failure occurred after the vehicle had been inspected under the recall and I had been advised that it was not affected. I am concerned that my vehicle may have been incorrectly excluded from the recall or that the recall does not adequately identify all affected vehicles. The sudden loss of propulsion at highway speed presented a significant safety risk and warrants further investigation. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Engine stopped working while driving 65 mph on I435 Kansas City. Engine failure had to pull over in 3 lane traffic to get off of roadway. Engine just stopped working. Had towed to GM dealer who performed full engine replacement. 6.2 L . No warning. Just stopped working. Safety traveling on 3 land highway engine stopped with no warning had to work way over the shoulder with no engine.