GMC Complaints

Check engine light is on took vehicle to dealership 10/13/2023 vacuum booster sensor replaced (37,435 miles) $0 GM Covered cost 12/9/2024 brake vacuum pump replaced (56,456 miles) $0 extended warranty 1/8/2025 vacuum booster sensor replaced (57,087 miles) $252.48 not covered by warranty Check engine light is on 10/11/2025 took to dealership. They were unable to find issue light was off, was told that GM had recommended several things that could be the cause of light coming on still could not find issue. Last thing GM and dealership recommended was to replace the battery. Cost $104.00 Check engine light came on 10/25/2025 while returning home from Tennessee to Michigan, light came on in Louisville, KY. Had it scanned, booster sensor was the cause. Called AAA had them replace battery light went off. (as you know that if you do that it reset the computer not surprised light went off drove rest of the way home to Michigan) Cost of replacement battery $295.00 Check engine light came on again 11/2/2025 my best bet is that it is booster sensor again. NHTSA and GM need to fix this issue. I have not lost breaking ability yet but the horror story that I've read on this site scars me. WHAT ARE IS NHTSA AND GM GOING TO DO WAIT UNTIL SOMEONE IS KILLED BECAUSE OF THIS ISSUE !!!!!!!!

The vehicle underwent a recall inspection on September 8, but on October 2, the vehicle still experienced a serious engine failure. The vehicle was undrivable, and the dealer inspected it and opened a TCA case. However, General Motors stated that it had passed the recall test and was not covered under special warranty, and asked me to pay $5,000 for vehicle repairs. I believe this is an engine malfunction related to the recall, and the manufacturer should replace the engine for me free of charge and refund my 5,000 .

The vehicle has experienced numerous losses of power, it has nearly stalled during normal operation, there is a horrible knocking noise coming from the engine. I have had the vehicle into the dealership who state they are unable to recreate the issue, and since the vehicle has been turned off the recorder shows noting either. They have performed an inspection and changed the oil, but the vehicle still has the issue. It knocks and shudders like it's cold, it comes very close to stalling and then seems to recover, this has happend twice while making left hand turns, it has completly lost power even while depressing the gas, but again they indicate they can't recreate it, so there is nothing they can do. I am scared for my safety, and that of the child I drive daily. There have been several instances in the last few months.

My 2022 Yukon with the 6.2 engine locked up on a mountain highway in Wyoming. There were no prior symptoms — the engine suddenly lost power and shifted into neutral, forcing me to pull over. The biggest issue was that once the vehicle stopped, it couldn’t be shifted into neutral, which could have caused a secondary collision. The dealer who sold the vehicle didn't treat this seriously and sold as inspection passed vehicle.

Was driving at about 55 mph and vehicle popped up with warning and said shift into neutral to restart. I tried to and all power turned off. This was at around 8 p.m. so no headlights or anything. Luckily got it stopped without hitting anything. Had vehicle towed and motor was locked up. Spun bearing they said. Same issue apparently as other 6.2 liter engines have been having.

I was driving home and about 10 minutes into my drive I got a notification about my steering assistance being disabled. When I arrived home about 10 minutes or so later and went to shut my car off I noticed that a very loud fan sound from the hood of my vehicle began roaring. I restarted my car and it went away. I looked at my temperature gauge and it was all the way on C. I tried shutting my car off again and the loud electrical fan sound picked right back up again. I stayed in my vehicle while it was turned off waiting to see if it would stop while trying to call for answers. I couldn’t risk having a dead battery for work tomorrow morning. After what was about 6-7 minutes the electrical fan finally shut off. Turns out my aunt JUST had this exact same issue with her 2021 GMC Acadia as well. According to Reddit MANY people are having this issue yet there is still no recall for this problem. My car is only at 85K miles, has always been dealership maintained and has never had any issues like this until now. If this is a wide spread make and model issue a recall should have been issued.

I experienced lifter and camshaft failure on my 2020 GMC Sierra equipped with the 6.2L V8 engine at approximately 72,000 km. GMC denied warranty coverage as my factory warranty had expired only four months earlier. The repair cost me nearly $10,000 out of pocket. My vehicle has been meticulously maintained with regular oil changes performed at my local GMC dealer every 5,000 km, and it has always been fueled with premium gasoline as recommended by the manufacturer. The engine failure was sudden and unexpected. All lifters and the camshaft were replaced during the repair. Since the repair, I have noticed intermittent RPM fluctuation under light load conditions. I am currently working with my dealer to diagnose whether this issue is related to the recent engine repair or a transmission flush that was performed at the same time. I am extremely disappointed in GMC’s handling of this situation. Despite this being a well-documented issue with the 6.2L engine, I received no goodwill assistance or warranty consideration from GMC. While my dealer provided a partial discount on parts and labor, I was still responsible for nearly the entire repair cost. I hope GMC and NHTSA will review this matter closely, as owners should not be facing such expensive failures on well-maintained vehicles with this engine.

While driving the vehicle at approximately 40MPH the motor made a tapping sound, I was able to pull into a parking lot and have the vehicle towed to the dealer. The dealer told me that the vehicle was out of warranty and appeared that under initial inspection the would have to rebuild the motor due to a lifter failure at the estimated cost of $18,000. I had the vehicle towed to a reputable repair shop and after the did a tear down to the small block they determined a bent push rod and broken lifter, all pushrods and AFM lifters were replaced at the cost of $10,754. dollars as invoice shows. The issue occurred again on 10/25/25 causing catastrophic failure that will cost me a complete engine replacement.

My wife was driving at highway speeds with all are kids when the trucks motor suddenly loss all power all check engine lights illuminated and what I'm assuming had major engine failure causing rod knock.

This issue affects all vehicles in the GMC lineup. The forward collision alert system is so sensitive that it gives false positives constantly which causes 2 major safety issues with the vehicle. First is that it brakes without warning and when completely unnecessary. The 2nd is that vehicles like mine with a heads up display, have the entire display flash a very bright yellow blocking the field of vision to the front of the vehicle. The system is not able to be disengaged permanently and can cause rear end collisions by braking when no obstacle exists and blocks the ability to see in front of you via the heads up display warning.