2023 GMC SIERRA 1500 Complaints

I am a Canadian owner of a 2023 GMC Sierra 1500 AT4 equipped with the 6.2L L87 engine. VIN: [XXX]. I purchased the vehicle new. I am reporting this because my experience appears directly relevant to NHTSA Engineering Analysis EA26005 concerning L87 engine failures after Recall 25V-274 remedies. The GM recall remedy/oil change was performed at 103,503 km (64,315 mi). At 130,695 km (81,210 mi), the original engine suffered a catastrophic failure and completely seized. The engine could not even be rotated manually at the crankshaft. GM replaced the complete engine. At 142,541 km (88,571 mi), only 11,846 km (7,361 mi) later, I returned for the first oil change on the replacement engine. I told the dealer that the vehicle was behaving abnormally, especially the transmission, which was shifting strangely. After inspection, the dealer determined that the replacement engine was beginning to seize. The increased resistance from the engine was causing the abnormal transmission behavior. The complete engine was replaced AGAIN. The vehicle now has 148,560 km (92,310 mi), meaning this second replacement/third engine has only about 6,019 km (3,740 mi). I am again noticing symptoms similar to those that occurred before the previous engine failure. I cannot confirm that this engine will fail, but after two previous engine failures, I am very concerned. This vehicle has therefore had two L87 engines: the original engine and one replacement. One replacement engine itself began seizing after less than 12,000 km. I believe these repeated failures after both the recall remedy and a complete engine replacement are directly relevant to EA26005 and the safety risk of sudden loss of propulsion. I have GM/dealer repair orders documenting the recall service and both engine replacements and can provide them upon request. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Truck went into limo mode while driving and required valve in transmission to be replaced. Went from driving normal speed to only being able to go about 15 miles and hour. Was repaired got the truck back and the next day was on the interstate in the fast lane and the truck again had speed issue reduced speed and had to coast off interstate. This time entire valve body had to be replaced. Have gotten truck back and still have hard shifting in the transmission at times. Engine was checked for recall and now I have to pay a much higher oil change price due to a GM issue. This was not a known cost when purchasing this truck.

13 unresolved problem codes relating to hard engine starting,rough engine running,vehicle initiating safe mode operation, upon a highway trip. P0016 engine code detected and Onstar messaged for immediate service. No resolution at dealership , after resetting codes an additional 9 are active / pending at 2nd dealership visit. Abnormal engine operation since , dealership advises a hard failure has to occur before a resolution can be instituted. Similar advice from GMC direct phone call in help line.

Complete engine failure. Safety is was put at risk one engine lost propulsion on a bridge with no median. Truck towed to a GM dealer that inspected it and replace the engine. Check engine light and low oil pressure light came on approximately 30 seconds before the engine died.

During a family camping trip, our engine seized without warning — a failure directly tied to an active GMC recall. Despite this being a manufacturer defect, GMC roadside assistance refused to provide full support and informed us that we were responsible for towing our trailer home. This placed an unreasonable financial and logistical burden on us during an already distressing situation. To make situation worse when we brought the vehicle to O’Meara GMC for the recall repair Four months prior.They kept our truck for an entire week, only to inform us that their “solution” was to put heavier-weight oil in the engine. This is not a recall repair. It is not a fix. It is a temporary workaround that demonstrates clear incompetence and an inability or unwillingness to replace the motor as required under the recall. O’Meara GMC failed to perform the recall repair, failed to replace the engine, and failed to provide any meaningful resolution. Their actions have left us with a vehicle that is unsafe, unreliable, and not repaired according to GMC’s own recall standards.

The contact owns a 2023 GMC Sierra 1500. The contact stated that while driving approximately 40 MPH, the check engine warning light illuminated, and an oil message was displayed. The vehicle stalled and was unable to be restarted. The vehicle was towed to a dealer where it was diagnosed and determined that the engine needed to be replaced. The vehicle was repaired, but the failure reoccurred approximately two weeks later. The vehicle was taken to a different dealer but was not yet diagnosed. The manufacturer was notified of the failure. The failure mileage was 29,000.

August 5th, 2026, I was driving South on I-55 between Hammond and Ponchatoula at 70 mph when the top grill trim (Bezel) flew off, hit (and cracked) the windshield, and landed somewhere behind my traveling vehicle.

I, [XXX], am currently getting my engine replaced for the 1st time because of An engine failure. Engine completely shut down in the mountains while I had my 3 young kids ([XXX], [XXX] & [XXX] old) on our way to our vacation. 102 degrees outside no ac, no water for 4 hours until a tow truck finally came. The kids were scared for their life due to being on the side on the road, hungry with nothing to do but wait. Literally had just enough clearance to get on the side of road where vehicles drive-55-65 mph. Avenal, Ca to be exact. What’s the best way to get my money back? I do not want to continue to deal with these problems on the road with my little ones. The dealership is currently looking to replace my engine and waiting on parts. There has not been an official date I will get my vehicle back. Thank you in advance. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Driving on I-75 with cruise control engages. Vehicle began decelerating. Pulled over onto emergency lane. Engine idled roughly. Shut down. Attempted one restart unsuccessfully.

Sudden loss of propulsion while driving on I-75 with cruise control engaged. Vehicle began to decelerate. Pulled off onto emergency lane. Engine was idle-ing roughly. Would not increase rev when gas pedal pressed. Shut down. Tried one restart. Unsuccessful.