GMC Terrain Complaints
3,167 consumer complaints on file.
- #11716716February 9, 2026ENGINE, SERVICE BRAKES, HYDRAULIC
The contact owns a 2025 GMC Terrain. The contact stated that while his wife was driving approximately 40 MPH on wet roads, the brake pedal was depressed, but the brake pedal was stiff, preventing the vehicle from slowing down as intended. There were several unknown warning lights illuminated during the failure. The accelerator pedal was released, and the vehicle rolled to a stop. The vehicle was turned off and restarted, but the check engine warning light remained illuminated. The vehicle was pulled over to the side of the road and turned off. The vehicle was then towed to a dealer, where it was diagnosed, and determined that the brake control module needed to be replaced. The vehicle was repaired, but the failure reoccurred approximately 7 months and 2 weeks later. The manufacturer was notified of the failure. The failure mileage was approximately 1,126.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11715861February 5, 2026ENGINE
Rear main seal blow out
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11715646February 4, 2026ENGINE
On January 31, 2026, while driving on the highway, my 2017 GMC Terrain suddenly began shaking as if it was going to stall. Thankfully, I managed to exit the interstate before the vehicle lost power. Luckily, when this happened, it "only" blocked traffic on a side road. The Terrain was towed to my garage. The mechanic called to inform me that the vehicle was out of oil -even though it was not due for servicing, nor did a “check oil" warning appear. He noted that this was not the first time he had seen this problem occur with this particular make and model: the PCV valve had frozen due to recent cold weather, which led to the rear main seal fracturing, causing oil leaking. In addition, the manifold had also cracked. He explained that repairs would be costly given the labor needed to remove the transmission and perform other related tasks. He recommended that I "Google" the problem to gain an understanding of the time involved to complete this repair. My research corroborated that this was a very labor-intensive undertaking. More concerning was discovering an abundance of cases documenting this failure -as well as class action lawsuits- which underscores the fact that GM knows about this issue but refuses to address it. I am not sure why there hasn't been a recall—though perhaps that's a question for people much smarter than I am. Now, after spending thousands of dollars, I have a vehicle with an oil life monitoring system that doesn't function as intended—and worse, I know this could happen again.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11715695February 4, 2026ENGINE
Traveling on the expressway, engine made wearing noise, reduced engine power and complete engine failure while driving. Rear main seal blowout due to a defective PCV system freezing. It is a known issue for GM2.4L engine especially in cold weather leading to massive oil loss and catastrophic engine damage. This has been confirmed by a GM authorized dealer.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11715704February 4, 2026SERVICE BRAKES, ENGINE
My family and I were returning home from vacation in another state, and while we were driving on the interstate, an alarm popped up on the DTC stating ruduced engine power. I tried to start slowing down so I could take the next off ramp and could not push the brake pedal in. I had absolutely no brakes trying to slow down from interstate speed. I was able to pull into a gas station parking lot while avoiding other vehicles. I was very lucky not to get in an accident. I had to have it towed to the nearest service center and was charged nearly $4000 for repair. The car has not ran right since we recieved it back. I called them back to let them know and was told the only way I would not have to pay to have it looked at was to bring it back to them. That shop was four and a half hours away from my house. The car was less than twenty miles out of the warranty when it broke down (nine miles to be exact), then they lied on the the paperwork and put the milage after they test drove it.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11715519February 4, 2026ELECTRICAL SYSTEM
The infotainment system is not working. It has the "black screen" issue.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11715195February 3, 2026ENGINE
excessive oil consumption....caused engine to fail....yes, car is available for inspection ...caused the car to lag and initially break down without any warning lights ...confirmed form dealer new engine needed...law suits in other states have proven that this seal problem has been known to GMC for years and they haven't repaired these faulty parts...again, no warning lights came on...please assist
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11714993February 2, 2026POWER TRAIN
SUVs check engine light turned on and went into reduced power mode, it has been very cold for approximately a month. Code P0299.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11714938February 2, 2026POWER TRAIN
Transmission dropped complete out of gear while driving. Got vehicle moving again. Took to dealership. Found complete internal transmission failure at 6779 miles. Transmission replaced with new unit. New transmission has erratic / hard shifts. Found replacement transmission leaking fluid due to front pump / porous case at 14800 miles. Customer Satisfaction Program N232433890 issued May 16, 2024
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11714905February 2, 2026POWER TRAIN
The contact owns a 2026 GMC Terrain. While driving at 28 MPH, the RPM became elevated to over 3,000 RPM. There was no warning light illuminated. The contact immediately pulled over and then resumed normal operation after the failure. The vehicle was taken to the dealer to be diagnosed; however, no cause for the failure was found. The contact was advised to bring the vehicle back to the dealer if the failure reoccurred. Approximately one week after the initial failure, while driving approximately 30 MPH, the transmission unexpectedly downshifted to L2. There was no warning light illuminated. The contact pulled over and restarted the vehicle, and the vehicle was taken back to the dealer. A diagnostic test was performed, and the contact was informed that the transmission needed to be rebuilt. The manufacturer was notified of the failure and was provided a case number. The vehicle remained with the dealer unrepaired. The failure mileage was approximately 1,300.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11714544January 30, 2026UNKNOWN OR OTHER
I own a 2020 GMC Terrain with approximately 110,000 miles. While driving in winter, the vehicle suddenly lost cabin heat and defrosting capability. The temperature gauge began fluctuating and the cooling fans continued running after the vehicle was shut off. A mechanic diagnosed the cause as a cracked radiator that allowed coolant to leak out, which is a known frequent failure on this model. Because the heater stopped working in sub-freezing temperatures, this created a safety hazard due to lack of defrosting and heat while driving. The failure occurred without warning, and no coolant warning light was displayed before the heater stopped working. The vehicle was not overheating at the time, but the loss of heat and defrost made winter driving unsafe.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11714113January 29, 2026FUEL/PROPULSION SYSTEM
Turbo boost went out in my vehicle and 3 others with the same engine, different makes/models. Vehicles were serviced at Grayling Car Care 4430 M-72, Grayling, MI 49738 (989) 348-3200. Significant power loss, sluggish acceleration, poor fuel economy, and often strange noises (whining, grinding), accompanied by blue smoke from burning oil and a lit check engine light, with the severe risk of catastrophic engine damage from broken parts entering the engine if driven, requiring prompt replacement. It's generally unsafe to drive with a bad turbo, as metal fragments can destroy the engine.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11714193January 29, 2026ENGINE, UNKNOWN OR OTHER
The PCV valve froze which caused pressure to build up in the rear main seal to fail. Causing oil to leak out of the motor. Hence the motor won't hold oil.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11713540January 27, 2026ENGINE, FUEL/PROPULSION SYSTEM, STRUCTURE:BODY
I noticed a sticker in driver door stating recall however no evidence. The vehicle will not pull hills, back up on a hill and will not accelerate over 25 miles per minute. Dangerous to drive on roads. Took vehicle to a GMC dealer for diagnostic test, received the report for what the report found. Took the report to auto shop to get repaired however the vehicle still continues with same issue. Took the vehicle to another auto shop. I was informed of some differences added issues. I had those issues fixed. The vehicle still running the exact way after all of the repairs. The top hood on the vehicle paint starts peeling after a year of owning it. I purchased the vehicle at Kia of Gardendale 2020. No one had any answer regarding the situation. Very disappointed with a GMC vehicle. I just want to know the mystery.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11713435January 26, 2026ENGINE
The contact owns a 2017 GMC Terrain. The contact stated that the vehicle failed to start. The vehicle was towed to an independent mechanic, where it was diagnosed with engine failure. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The vehicle was towed to the dealer, where the engine diagnostic result was confirmed. The vehicle was not repaired due to the cost. The contact stated that two years prior to the failure, the vehicle failed to accelerate as intended while depressing the accelerator pedal and the vehicle stalled. The manufacturer was not notified of the failure. The failure mileage was unknown.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11713477January 26, 2026ENGINE, FUEL/PROPULSION SYSTEM, LANE DEPARTURE: BLIND SPOT DETECTION
The engine light came on while driving, saying “engine power reduced”. It barely accelerates, RPMs go over 5, it chugs when driving. Taken to an independent service center.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11712586January 22, 2026ENGINE
around chirstmas, Was driving on the highway and the car threw a "reduced engine power" warning and went into limp mode. Check engine light came on. Car asymptomatic prior. got the code pulled and it said turbocharger under boost. The next day the check engine light went out and car was running appropriately. Took the car on the highway again and the car threw the "reduced engine power" warning and went into limp mode again in the middle of freeway traffic. It is a safety concern due to the engine going into limp mode in the middle of high speed traffic. I easily couldve caused an accident putting both myself and others in danger by the engine cutting the power in the middle of the freeway. The check engine light only comes on while going at freeway speeds. The light will then go out overnight and come back on the next time i go back on the freeway at 70-80mph speeds. I have taken it to one shop which reported an oil leak coming from the turbo both inside and outside and that it needed to be replaced. I have read several different forums of other users of the same year, make, and model experiencing the same issue. the car is only a few years old and the likelihood of a turbocharger being bad is uncommon but a major safety concern considering this happened out of nowhere with no signs or symptoms leading up to this.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11712537January 21, 2026ENGINE, ELECTRICAL SYSTEM, POWER TRAIN
I am filing this complaint to report a catastrophic engine failure involving my 2017 GMC Terrain equipped with the 2.4L Ecotec engine, which I believe is the result of a known manufacturing defect related to excessive oil consumption and premature internal engine wear. At approximately 88,000 miles, my vehicle experienced severe engine failure, including excessive oil consumption, timing chain failure, and complete engine failure, which has been confirmed in writing by a licensed repair facility. The shop determined that the engine failure was caused by oil starvation resulting from excessive oil consumption, leading to internal engine damage and timing chain failure. This failure occurred without warning and rendered the vehicle unsafe to operate. Sudden engine failure creates a serious safety risk, including loss of power while driving, inability to accelerate, and increased risk of collision. This engine failure matches a well-documented defect pattern involving General Motors’ 2.4L Ecotec engines, which have been the subject of class-action lawsuits, settlements, and jury verdicts related to premature piston ring wear, excessive oil consumption, and resulting engine damage or failure. These issues have been widely reported in Chevrolet Equinox and GMC Terrain vehicles within my model year range. My vehicle was properly maintained, and this failure was not the result of neglect, misuse, or normal wear and tear, but rather a latent manufacturing defect that manifested after the warranty period but well within the reasonable life expectancy of the engine. I am requesting that NHTSA formally document and investigate this defect, as it presents a significant safety concern for drivers operating vehicles equipped with this engine. I also request that General Motors be required to address this defect to prevent additional engine failures and potential safety incidents.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11712292January 20, 2026UNKNOWN OR OTHER
The radio dead out randomly. Which means the back up camera is non working. I wasn’t able to see a stump and hit it. Doesn’t seem safe. Like what would has happened if it was a person instead and they like the stump was in my blind spot while backing up. I feel like this is a safety issue. I have looked it up online and found out this is a common issue with these vehicles.
- Crash:
- Yes
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11712053January 20, 2026UNKNOWN OR OTHER
Complete engine failure @100,600 miles Engine power reduced and lost compression transmission module failure Will not exceed 20mph
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0