GMC Complaints

Informant system tells me that the engine oil is low every time right at about 1,000 miles after I change the oil. There have been times where the engine has hesitated to accelerate shortly after receiving the message. I've taken truck to be serviced with no oil leaks found. I purchased this truck with 21,000 miles on it, and it's been doing this ever since I've had it.

The engine failed and started burning oil at a rate of 3 quarts every two weeks. The vehicle is currently at the GMC dealership having the engine rebuilt at a cost of over $15,000. The vehicle has approx. 116,000 miles at time of failure, so it is outside of the manufacturers warranty. The GMC dealership (Fred Anderson Greer) has photos. The engine is a 6.2L but not currently under recall as it is a 2020, the recall includes 2021 - 2024 models.

The contact owns a 2019 GMC Yukon XL. The contact stated that while driving approximately 68 MPH, the vehicle vibrated abnormally, with a knocking sound coming from the engine compartment, with the check engine warning light was illuminated. The vehicle was taken to a certified mechanic, who diagnosed the vehicle and determined that lifter #7 had failed and needed to be replaced. The contact stated that all the lifters were replaced. The contact stated that approximately 5 days later, on October 2, 2025, while reversing, there was a burning odor with black smoke coming from the exhaust pipe. The vehicle was towed to the mechanic and was diagnosed with coolant intrusion into the engine. The contact was informed that the engine needed to be replaced; however, the warranty only provided the replacement of 2 head gaskets. After 7 days of having the vehicle, while driving approximately 68 MPH, the vehicle started shaking with the check engine warning light illuminated. The vehicle was also idling roughly. The vehicle was towed to the mechanic and was diagnosed with fuel pump failure. The fuel pump was replaced; however, the vehicle was idling roughly, and there was an intermittent misfire in cylinders #1 and #6. The dealer was unable to identify which cylinders needed to be replaced. The contact discovered information of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the VIN was not available. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was 127,000.

My 2020 GMC Sierra 1500 Denali with the 6.2L L87 V8 just began experiencing a new rough idle with intermittent RPM dips. There are no engine codes or warning lights. Idle drops are noticeable, suddenly began this week. I am concerned due to ongoing NHTSA Engineering Analysis EA25-007 involving this engine. Some owners reported engine failure with little warning. The truck has right over 68,000 miles on it and has had every oil changed performed at a GM dealer. I have had to top off the oil between cycles and always used the recommended oil, being the Dexos Gen 3 due to the truck burning a small amount of oil. More detail on a possible cause. I believe it would be worth investigating the DFM technology. I will be performing a fuel cleaner and possibly a lifter cleaner and/or additive. I would like to tune the truck and turn off the DFM since this is what I have read causes the truck to burn oil and damage the lifters. However, I will wait until this Analysis is completed before deciding to change the truck's stock tunes.

An AC clutch/compressor malfunction. No cold air, unusual noises (grinding, squealing, rattling), metal shavings, burning rubber smell, engine stalling. No warning lamps or messages ever appeared. The problem was serviced at independent service center. The nearest GM dealer is more than 40 miles away from me. Did not drive vehicle and seeked professional help immediately.

Routine oil change by professional local mechanic. Upon completion we were told that the vehicle would not turnover. The mechanic diagnosed and found that were 2 recalls for our vehicle - one for the fuel pump module and one for the engine. We had our vehicle towed to the local GM dealership. They then replaced the fuel control module. GM tried to manually crank over but engine seized once again. We spoke to the GM Advisor prior to this and were told that our vehicle was not part of the engine recall because our VIN was not listed as part of it even though our vehicle had the same exact issues as described in the engine recall and was for the exact year/make/model of the engine. The dealer quoted us $14,896 to replace the engine. They stated they would submit a Goodwill claim to GMC to help discount the cost to repair/replace the engine. The dealer called back later that day and said GMC would be willing to cover 30% of the cost so our expense would be around $10,000. All this for a vehicle we've only driven for less than a year and a half. The vehicle went in for a routine oil change and has never had any issues prior to this. This happened suddenly without any sort of warning. To make matters worse, our powertrain warranty expired a day or two before this occurred. We are still trying to fight with GMC to cover this engine failure. The car has less than 75,000 miles and is only used for basic personal needs like driving to school and the store so it is shocking that the engine would suddenly fail like this and to make matters, the manufacturer refuses to take responsibility for it and to cover it under the recall even though there has been known widespread issues with this engine.

The engine oil drained into the radiator from a flaw in there design in which outrageously high labor cost for the owner of the vehicle they put a rubber house in the radiator in which leaked without any warning indicating that there was a problem with the oil nor the radiator coolant system. repairs are in the thousand and I as a consumer should have this matter resolved at no cost due to bad design cost they should have made a oil cooler with its own separation compartment like the transmission cooler because they are replaceing everything else what about the engine itself thats still going to be contaminated like all the replacement part, seal hoses,and radiator, coolant, and thermostat. How can just parts be contaminated but not the engine? They are just replacing things that costs alot. This is a drive train issue, there were no oil in the engine.

2018 GMC Sierra started having shuddering/jerking/jumping problems at around 60k miles. This problem occurs while driving on straight aways, going uphill and while in drive at a stop sign/light. When the gas is accelerated the truck then hesitates and jerks/jumps. We have taken it to the GMC dealership and paid for the diagnostics and were informed “the problem wasn’t severe enough”. The truck has only been serviced by GMC dealership. So after failed attempts with GMC service department we have taken it to a local small auto shop and they automatically said it was the Drive Train and needed to be taken to a transmission shop. We have been GM owners for decades and are so disappointed in the service received from them.

The contact owns a 2020 GMC Sierra Denali. The contact stated that while stopped at a traffic light with the brake pedal depressed, the vehicle shut off unexpectedly. There was no warning light illuminated. The contact made several attempts to restart the vehicle; however, the vehicle failed to restart. Due to the failure, the vehicle was towed to the dealer where a diagnostic test was performed. The contact was later informed that the engine had seized due to engine bearing failure, and the contact was provided an estimate for a new engine. Upon investigation, the contact discovered NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling) and linked the recall to the failure. The manufacturer was notified about the failure and the recall, and the contact was informed that the VIN was not included in the recall. The vehicle was not repaired and remained with the dealer. The failure mileage was approximately 190,000.

ENGINE BURNING OIL AND BLOWING WHITE SMOKE OUT TAIL PIPES. HAVE TO ADD OIL EVERY 1500 MILES OR SOONER IF TOWING. HAS BEEN AN ISSUE SINCE FIRST OIL CHANGE. VEHICLE IS NOW AT 88057 MILES