GMC Complaints

Noticed a coolant leak on drivers side and took to dealership was told was the upper radiator hose but was unable to make repairs due to national backorder and only suggestion was to drive until parts come in and keep a check on the coolant level, My truck only has 28,708 miles and shouldn't have to keep an eye on coolant level I feel that is very unsafe

My name is [XXX] I have a 2019 GMC Yukon Denali with 226,000 miles my engine has went out do to the same issues that's going on with the GM motors right now. I have brought it in to Courtsey GMC and they told me my engine needed to be replace do to oil pressure problem cylinder 8 was bad. After taking the engine apart they notice the problem. my phone number [XXX] email [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

OnStar Module is disabled, this is a key safety feature, one of the reasons I purchased this vehicle.

Fuel management system caused a lifter to fail (stuck) which resulted in camshaft damage at 77,611 miles. GM refused to cover the repair, although there is a pending class action lawsuit against GM for this very issue. Truck was repaired at a GM dealership - Sunrise Collierville, TN. Repair costs was approximately $7,000. This occurred during a 2.5 hour road trip which put lives at risk. The truck began to vibrate, and the check engine light came on. There was no other warning before the failure occurred. No police or insurance were involved. This occurred on 9/27/25. It took the dealership 32 days to diagnose and repair the issue. Thanks.

Picked up vehicle from Dealership new, with 12miles on the odometer. During the trip home (over 150+ miles each way) and at 54 miles a "Forward Collision System Unavailable" warning message appeared on the dash. Stopped for coffee and restarted the vehicle and the error cleared. It re-appeared at 235 miles, and again at 427 miles along with an OBD error P0700 @cycle#763, Occurrence Cycle #2608. Returned the Vehicle to the dealership service department for repairs. The vehicle was returned and we took the truck on our first trip to Yosemite and while driving it the cruise control released the throttle times driving on a 4 lane Hwy 152. Then on the backside of Pancho Pass we entered the town of Los Banos. While driving in a 45 MPH section of Hwy 152, with no other cars in front or behind us, the truck performed an emergency stop. It applied the brakes at maximum force causing the front to dive hard and the rear tires to lose traction with the antilock cycling the brakes on and off, causing them to slip bringing the truck to a stop. At no time did the dash or the HUD display flash the collision warning or any error messages, I applied throttle and moved the Truck off the Hwy to the side of the road. Checked all pages on the dash for any indication of problems, and we drove to a parking lot inspecting the truck top to bottom to see if there were any obstructions, damage to the bumper sensors, or windshield. Returned the Truck to the dealership a second time for repairs. Received the vehicle back and during the drive home we Stopped for Dinner in San Jose and the "Forward Collision System Unavailable" returned again. Returned the vehicle for service a third time and notified Manufacture of the issues.This is a Major safety defect that GM cannot seem to repair. Current mileage of vehicle 3098.

The contact owns a 2021 GMC Yukon. The contact stated that while driving at an undisclosed speed, the contact noticed that the front windshield was extremely blurry. In addition, the contact stated that it was a safety failure, especially while driving at night. The contact stated that while driving at night, the failure was extremely unsafe. The vehicle was taken to the dealer, and it was confirmed that the front windshield was defective. The contact was informed that the front windshield needed to be replaced. The vehicle was not repaired. In addition, the failure occurred previously in June 2023, and the repair was covered under warranty. The manufacturer was made aware of the failure, and a case was filed. The repair was denied. The failure mileage was approximately 25,000. The VIN was unavailable.

The contact owns a 2024 GMC Sierra 1500. The contact stated that while driving approximately 70 MPH, the vehicle started losing automotive power and stalled. The contact frantically maneuvered the vehicle across three lanes of highway traffic to get to the right shoulder and park the vehicle. During the failure, the check engine warning light and several other unknown warning lights illuminated. The vehicle was later towed to the local dealer. The cause of the failure was not yet determined. The manufacturer was also notified of the failure. The contact had previously received a letter regarding NHTSA Campaign Number: 25V274000 (ENGINE AND ENGINE COOLING). The contact stated that the vehicle had experienced the failure listed in the recall. The failure mileage was 48,301.

I am writing to express my significant concerns regarding the recurring issues with my 2024 Denali 6.2, which has been subject to multiple service visits since reaching 7,000 miles. Despite these visits, the underlying problem remains undiagnosed and reoccurs shortly after I retrieve the vehicle. Following the second oil change, the engine developed a persistent ticking noise. Over the past 13 month, I have invested over $200,000 with your dealership in the past 5 years!. My truck was recently held for two weeks for service. After I lodged a complaint, the General Manager suggested I seek service elsewhere. This recommendation was made after I responded to an email stating that, following the completion of repairs to the headliner, third brake light, and brakes/rotors, I would no longer be utilizing Crain's services. The headliner sustained water damage due to improper installation by your technician, and fingerprints were also evident. I firmly believe in transparent communication regarding service progress, which was notably absent in this instance. Both the General Manager and Service Manager deferred responsibility, instructing me to contact GM directly, only for GM to inform me that direct contact was inappropriate. This resulted in a continuous cycle of unaddressed concerns with the service manager. Currently, I am operating an $80,000 vehicle that has incurred damage from a technician and exhibits a ticking engine. Furthermore, the driver's side mirror, which was previously replaced due to shaking at highway speeds, is now exhibiting the same issue, despite a technician's assertion that this is normal. I also note that my brakes, with over 89% remaining, are beginning to squeak, which your team claims is normal. This assessment is difficult to accept.

I brought my 2024 Sierra in for its L87 recall. It passed. Two weeks later I had to bring it in for check engine light. They reset the system under a TSB that is known to occur with the l87 recall. Not a total of 300 miles of passing the recall I was driving and the engine started making a horrible noise and I started experiencing loss of power. I managed to get the vehicle safely parked. The dealer pulled the oil filter and said it had 100% metal contamination in the oil. The filter looked like a glitter bomb went off. It took 3 weeks, they replaced the engine with a remanufactured engine even though I told them new only. They also had to replace the radiator as it was polluted with metal.

I own a 2015 GMC Canyon that developed repeated and serious fuel-system and engine problems beginning around 56,000 miles. The vehicle experienced fuel contamination (water in the fuel system), multiple fuel injectors failing and sticking open, repeated misfires across several cylinders, and engine stalling/shutdown while driving. The truck was towed multiple times and repaired repeatedly by an authorized GMC dealership. Repairs included injector replacements, fuel pipe replacement, fuel-system cleaning, and related work. Technician notes show that broader repairs were recommended but not fully authorized, and the same problems continued to return. Despite the dealership later stating the vehicle was repaired, there is no written safety certification, no documented fuel-system integrity testing, and no GM engineering clearance confirming the vehicle is safe to operate. Because of the repeated failures and risk of fire or loss of power, I do not feel the vehicle is safe to drive. I personally paid over $6,000 out of pocket for fuel contamination repairs and spark plug replacement (not including towing), after warranty coverage denied some repairs as “water damage.” The vehicle has been unsafe or inoperable for extended periods. I am reporting this because repeated fuel-system failures and engine shutdown present a serious safety risk and may affect other vehicles of the same model.