2024 GMC Terrain Problems

Leaking transmission fluid at 7,000 miles. Technicians noticed during routine oil change at dealership.

The vehicle has experienced a recurring transmission-related defect that has required multiple repair attempts by an authorized GMC dealership. The transmission system has also exhibited fluid leakage. Despite prior repairs, the problem has continued to reoccur. Transmission and associated transmission fluid sealing components. The vehicle is currently available for inspection upon request. A transmission is a critical safety component that transfers engine power to the wheels. A transmission defect or fluid leak can result in loss of propulsion, hesitation, inability to accelerate as expected, unexpected changes in vehicle operation, or transmission failure while driving. These conditions could increase the risk of a crash, particularly when merging into traffic, crossing intersections, or traveling at highway speeds. Transmission fluid leaking onto roadways or vehicle components may also create additional safety concerns. The vehicle has been presented to an authorized GMC dealership for diagnosis and repair on multiple occasions. The dealership has acknowledged and attempted repairs related to the transmission. The vehicle has been inspected and repaired by authorized GMC service personnel. No police involvement. No independent inspection has been performed at this time. Manufacturer-authorized dealerships have documented the repairs. Symptoms included transmission-related concerns and transmission fluid leakage. The defect first appeared while the vehicle was under warranty and has continued despite repair attempts. The recurring nature of the transmission defect and fluid leak has reduced confidence in the vehicle’s ability to operate safely and reliably. The vehicle remains under warranty and has undergone multiple repair attempts without a permanent resolution.

Accelerator lag from any speed or stop. The care will take several seconds to hunt for the correct gear before shifting to accelerate. Or it will delay acceleration for several seconds while your pressing the accelerator. No SES indicator active. Mechanics can’t find issues. Other owners on forum a report the same sluggish behavior. These 1.5 turbo cars seem to need a software fix that they are not receiving. It’s like the drive by wire doesn’t register. Affects any gm vehicle with the 1.5 turbo and 9 spd auto.

Since purchase, this vehicle has consistently had an issue with the fuel system. When I call GMC they state only use no ethanol fuel. I wouldn’t have bought this car if that was the case. The dealership never said that when I was buying it. We replaced the entire engine for $11,000 because of a torn radiator hose, overheating and cracked a gasket. Now, the car is refusing to drive, giving engine power reduced

Since purchase, this vehicle has consistently had an issue with the fuel system. When I call GMC they state only use no ethanol fuel. I wouldn’t have bought this car if that was the case. The dealership never said that when I was buying it. We replaced the entire engine for $11,000 because of a torn radiator hose, overheating and cracked a gasket. Now, the car is refusing to drive, giving engine power reduced

On January 16, 2026 our 2024 GMC Terrain Denali experienced complete loss of power. The car was unmovable from the road, unable to shift into neutral, and unable to release the braking system in addition to the emergency brake. There were no warnings or indications prior to the vehicle's failure at 30,000 miles. The failure happened on a somewhat busy road with no ability to move the car out of the line of higher speed traffic. The cause was ultimately determined to be a fuel pump failure. The part was replaced under the 60,000 mile warranty, however, the issue relating got the fuel pump is known by GMC and has previously been litigated under a class-action suit. Therefore the "resolved" fuel pump issue remains a pressing and potentially dangerous and expensive issue.

I was driving about 55 mph with adaptive cruise control set to maintain a three-car-length following distance. It was raining, and when the vehicle in front of me slowed down, my vehicle did not detect it or slow down as expected. Instead, it continued accelerating, and I had to brake to avoid rear-ending the vehicle ahead.

This is a continuation for NHTSA campaign number 11711615. While an additional NHTSA complaint has been filed for the power train, this focuses specifically on design failures in the braking system. Our vehicle experienced a highway failure of the fuel pump, but due to the nature of a powertrain failure the car could not be put into neutral, only remain in park. The car was stranded in the middle of the road. As a AWD vehicle it similarly could not be towed as both wheels were fully locked. Tow informed us that there should be a manual release under the shifting column, however, this design safety feature had been removed in the 2024 iteration. The car was stuck on the road behind a blind turn on a somewhat busy road with vehicles typically traveling between 25-50 mph. The failure of a manual override for neutral and braking is a critical design failure that can lead to major accidents and death in the event of engine or transmission failure. There were no warnings, nor instructions or ability to get the car off the road.

The screen continues to go out. Screen contains many safety functions. When it malfunctions it is distracting.

a little over two weeks ago we were going to sidney to get groceries. it was hot that day so we turned the a/c on. fog started coming out of the vents, it looked like we turned on a fog machine! a few days later we were going to town, my daughter got in and the whole driver's side floor was full of water. there was so much of it we had to get the shop vac out to suck it up. I called the dealer where we purchased it from because it still under warranty. their shop guy was out for the week so they scheduled me an appt for the following week. by this time my speakers aren't working, my signal lights dont make any sounds when I use them and the floor is soaked again. on August 5th we took the car into high plains and left it. they said they worked on it for 4 hours and fixed the problem, some drain line was plugged with sludge and so the water knocked out a module or amp. I thot everything would be covered but then they said I'd have to pay because all of a sudden a mouse had causes that line to get plugged. I asked them for pictures because im turning it into my insurance company, and they said they would send them. they never have I requested the pictures 2x, once with Patrick the shop manager and then with Jeff presser, owner. Still today, nothing. Meanwhile yesterday here comes all the water on the floor again. We use this vehicle to haul my grandson to his therapies and medical appointments. he [XXX]. Now were worried that mold has started growing because even though were sucking up the water, the floor pad and carpet are still wet. I went online and have seen numerous people complaining about the same issue for years with these GMC Terrains, why hasnt there been a recall or national warning on this faulty problem? INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

This is a continuation for NHTSA campaign number 11711615. While an additional NHTSA complaint has been filed for the power train, this focuses specifically on design failures in the braking system. Our vehicle experienced a highway failure of the fuel pump, but due to the nature of a powertrain failure the car could not be put into neutral, only remain in park. The car was stranded in the middle of the road. As a AWD vehicle it similarly could not be towed as both wheels were fully locked. Tow informed us that there should be a manual release under the shifting column, however, this design safety feature had been removed in the 2024 iteration. The car was stuck on the road behind a blind turn on a somewhat busy road with vehicles typically traveling between 25-50 mph. The failure of a manual override for neutral and braking is a critical design failure that can lead to major accidents and death in the event of engine or transmission failure. There were no warnings, nor instructions or ability to get the car off the road.

The contact owns a 2024 GMC Terrain. The contact stated that while driving at various speeds, the vehicle was hesitating while accelerating. The contact stated that the vehicle was stalling, and the brake pedal was spongy. The vehicle was taken to the local dealer on several occasions, but the failure was not duplicated. The vehicle was not repaired. The contact stated that the failure persisted. The manufacturer was notified of the failure, but no assistance was provided. The failure mileage was 10.

The contact owned a 2024 GMC Terrain. The contact stated that while her daughter was driving 5 MPH on an intersection, another vehicle driving 40 MPH crashed into the driver's side of the vehicle, by the driver's side door. The driver's side curtain air bag deployed. The contact stated that the three holes on the air bag propelled burning air, which melted and burned through the three layers of clothing of the driver. The driver sustained second-degree burns and blisters on the hip. The contact picked up and transported the driver to Urgent Care, where medical assistance was provided. A police report was filed. The vehicle was deemed a total loss by the police officer. The vehicle was towed to a tow lot, pending assessment from the insurance company. The dealer and the manufacturer were not yet contacted. The failure mileage was approximately 55,000.

The contact owns a 2024 GMC Terrain. The contact stated that while driving at an undisclosed speed, the "Service Vehicle Soon" message was displayed, and the air bag warning light was intermittently illuminated. The vehicle was taken to the dealer; however, the dealer was unable to duplicate the failure. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 10,000.

See attached document for complaint.

The rear bumper on these suvs have no impact strip any impact even under 1 mph will damage the car significantly and a person could suffer whiplash.

While driving, the dash warning "service power steering" light up and my steering wheel locked making me unable to steer or manuever the car to safety. I was stuck in the middle of the road. I turned it off and on and was able to make it to a parking lot where the same safety messages illuminated four more times. I tried reversing and the same steering lock occurred again making me unable to drive the vehicle.

The contact owns a 2024 GMC Terrain. The contact became aware of a fluid leak underneath the vehicle. There was no warning light illuminated. The vehicle was driven to a local dealer, where it was diagnosed with a leaking torque converter seal, allowing transmission fluid to leak onto the ground. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was 3,787.