GMC Terrain 2024 — Reported problems

Factory powertrain programming actively locks out 9th gear (overdrive) during freeway driving at speeds exceeding 60–65 mph. The vehicle refuses to upshift from 8th to 9th gear, forcing sustained high-RPM operation during standard highway cruising.

The rear access closes on its own after sitting open for a period of time. I was sitting at grocery pick up with the access open. This caused it to close on worker at grocery pick up. It stayed closed and I had to hit the button to open it back it did not auto go back up when it couldn’t close.

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.

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

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.

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.

While driving the vehicle, the engine light came on, plus message board said service transmission and the engine went into limp mode. We let the car sit for awhile and checked the car. A scan said it was the pressure solenoid A in the transmission. The car sat for a day and the light was off. Drove the car and then it acted up again and now reverse doesn't work.

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.

See attached document for complaint.

this just started on it's own. back up rear camera shows distortion from time to time and appears to be getting worse or happening more.

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.

I WAS DRIVING THE CAR ON 12-22-25 I LOST POWER MY CAR DIED ON I94. BATTERY DIED THE DEARLSHIP COULDNT GET THE CODE. GOT THE CAR BACK ON 12-26-25. ENGINE LIGHT CAME ON CARRIE GMC REPLACED BATTERY . CAR BACK ON 12-29-25.. ENGINE LIGHT BACK ON 12-31-25 CAR BACK ON 1-8-26 REPLACLED CATALYTIC CONVEERTED AND OXY SENSOR. 2-20-26 DRIVING ON 1-94 LOST ENGINE POWER CAR BACK ON 2-25 FEUL PUMP AND FEUL LINE. DROVE 300 MILES ENGINE LIGHT BACK ON. BACK TO CURRIE GMC ON 2-26-26 UNTILL 3-2-26 REPLACRED HEATED OXYGEN SENSOR . 3-6-26 REPLACED CATELYTIC CONVERTER AND OXYGER SENSOR FOR THE SECOND TIME.

While driving several times smelt gas and car cut out engine came on and car stopped mid driving multiple times. Says they replaced fuel pump reset car etc

I bought my car in July of 2025 and since then my car keeps derating and reducing engine power while driving down the road at 70 miles an hour. It cuts out and decreases power. I took my car to the shop twice to have them tell it needed an update. I drove away and then the car does it again. Since December my car has down this decreased power, derated notice more than 30 times!! It is a safety risk for me and my family because you never know when it will happen on the interstate and when you will lose power. I have almost been rearended 3 times due to this issue and no one can seem to fix the issue.

Check engine light is coming on, indicating reduced engine power. Took vehicle to GMC dealer and they advised that the repair shop was getting assistance from the GMC Tech line to update a module to correct the issues. I was informed today that the high pressure fuel pump will have to be replaced, along with a hose or pipe to correct the issue. The vehicle has 57k miles on it. Upon researching the issue, I found that this has been a persistent issue with this model vehicle, dating back to 2020. It appears that it has not been resolved and the vehicles could stall or stop at any time. There is currently a class action lawsuit pending on this issue. Please help, this is dangerous

On Febuary 14 2026 I was driving on the feeder of the freeway with speeds of 50 mph my car suddenly down shifted in the middle of driving started shaking real bad stalled wouldn’t start wouldn’t go in gear at all would just die and say engine power reduced. This is after it had just been at the dealership and they said all I needed was an update. It had to be towed and the dealership said it was my high pressure fuel pump had failed. They replaced it and gave me the car back. I staled the next morning going to work on the freeway going 70 mph same exact thing happened except this time I could smell gas so strongly. I had to sit on the side of the highway until it was picked up due to gas smell and fear of fire. They say a bolt broke off of the high pressure fuel pump they just installed

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

Powertrain System failure while driving, causing complete loss of power on road. The car lacks any accessible manual overrides to put in neutral or turn off parking break. This leaves the car stuck in park with all four wheels locked in the middle of the road in an incident with no safe way to move or tow the vehicle. When attempting to tow car must be dragged, and parking brake continuously engages. Tow attempt took nearly 3 hours to saddle the vehicle in the roadway. Vehicle currently awaiting formal inspection/repair from dealership.

The contact owns a 2024 GMC Terrain. The contact stated that while his wife was driving at various speeds, the vehicle experienced a loss of automotive power. The check engine and transmission warning lights were illuminated. In addition, the contact's wife attempted to restart the vehicle; however, the gear shifter failed to move from neutral(N) and remained in Low Power Mode. The vehicle was towed to a local dealer, where it was diagnosed, and DTC: P0700 and P073E were retrieved. In addition, the contact related the failure to Technical Service Bulletin: PIP5974E; however, the VIN was not included. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 6,766.

The rear camera is displaying the top of the license plate! It wasn’t doing it when I first purchased the car. Dealer states it is normal. I do not agree.

FUEL PUMP WENT OUT AT 42K MILES.

My wife and I took our new vehicle on a 7k mile road trip this summer. Two times while on the freeway around 70 MPH, the sensors went wild. The cars auto break came on and red lights and collision warnings went off in the seat and the HUD. The vehicle slowed down to about 35 immediately! Then everything turned off and we sped back went down the road like nothing happened. Luckily there was no behind us or in front of us for a good distance. The thing is during both of the there was a car in the lane next to us at our 1 or 2 o'clock position. Perhaps the sensors. Mistakingly thought we were about to hit that car. Can these seniors be adjusted?

I purchased a new 2024 GMC Terrain in March 2024. At the time of the incident the mileage was approximately 18,000 miles. On [XXX], as I was driving on a MA state highway, the car lost power with no warning. I was able to "coast" into a parking lot where I contacted OnStar; a flatbed tow truck was dispatched and the car was towed to the local dealership where it was purchased. At this time, the car is still at the dealer as I was informed by dealer service consultant that it's a "massive" transmission job and parts were on back order from GMC for over three weeks. I specifically purchased this vehicle to be safe on my monthly trips to NY to visit grandchild. I no longer feel safe in this vehicle and have no guarantee this won't happen again. The fact that the transmission failed in 1 yr. old car at 18,000 miles is of great concern to me. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

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)

Vehicle shimmies upon acceleration from a stopped position.

car quit while driving could not control stopped across 2 lanes of highway almost was hit by big truck. Car would not start or go into neutral. When car almost started i put it into neutral and was pushed off of highway. dealer towed car and replaced fuel module at 25423 miles.

infotainment system safety issues. I have video. Multiple times per week when starting the car and backing the rear camera engages. When placing car in drive the rear camera never shuts off, the sound volume doesn't work, the entire infotainment system completely malfunctions. The safety is when attempting to function the controls the volume will turn up and not able to turn it down, the screen flashes and the infotainment systems controls on the steering wheel do NOT function. I've had it to the dealer and they indicate PIC6591A from March 3rd 2025 is logged. When contacting GMC corporate they refuse to give any information. The PIC spans across many GMC vehicles including 2019 models. Why hasn't this been addressed? My son drives a 2024 Chevy Trax and this car has no issues like the my car does. His car also doesn't have the transmission/gear shift buttons like the 2024 terrain does. Anyone else having issues with the GMC infotainment systems, black screen, malfunction? I have video.

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.

Unintended acceleration in forward and reverse: the vehicle experiences unintended acceleration both in forward and reverse. While driving in heavy traffic, the vehicle continues to maintain throttle position for approximately two seconds after releasing the throttle, creating a dangerous situation where the vehicle continues to accelerate towards other cars. This defect requires emergency braking to prevent a collision. In reverse , the vehicle also holds throttle position after the accelerator is released. This results in the vehicle unintentionally accelerating in reverse at a rapid pace. This requires the driver to depress the brake moderately to control the reverse speed. During this event the driver is fighting against the motor with the brake pedal until the vehicle decided to stop accelerating on its own.

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.

Driving on slightly uphill 55 mph highway, vehicle started jumping & losing engine power. Engine light came on, I made it to the top as it was slowing down. Pulled off to the side. Put it in park for a minute. Message showing on dash read - acceleration power reduced. Drove it on home (engine light stayed on) parked it & had it towed to dealership the next morning. Got a call from dealership the same afternoon saying the vehicle was ready to be picked up. Picked up later in evening from dealership. They left keys & paper in car for pick up. We still tend the paper left it in the box showing we picked it up. The vehicle drove good back home. Drove it the next day, As I was pulling out from a stop sign, it started jumping again for a few seconds. Got home & had my husband to drive it, as we were coming up a small hill, it started jumping & losing power again engine light was blinking at this point. Dash board read engine power reduced. My husband kept on the accelerater & when we got on top of the hill engine light went off & we drove it back to the dealership & left it to be checked again. They kept the vehicle for 7 days & said they were not able to find concern. We picked it up again. Drove it back home without any incident. It has been parked since we got it home.

Vehicle every other morning shows issue with blind spot assist. It keeps popping an error message and it has happened since I purchased it new. Took it multiple times to dealership and they cannot recreate issue. So it's been an issue since I bought it now.

The contact owns a 2024 GMC Terrain. The contact stated that while driving at an undisclosed speed and preparing to complete a left turn, there was an abnormal pop coming from underneath the vehicle. No warning lights were illuminated. The vehicle was taken to the dealer, who determined that the driveshaft had fractured. The vehicle was repaired. The contact stated that several days later the contact heard a loud pop, prompting the contact to take the vehicle back to the dealer, who was unable to duplicate the sound. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 1,200.

Vehicle was running but transmission was in PARK. Suddenly on screen in front of driver this message appeared: BRAKE SYSTEM FAILURE 43MPH TOP SPEED WARNING SERVICE ESC. Vehicle was not moving. Engine was running but vehicle was in PARK. I had to drive it home. Very difficult to stop. Brake pedal vibrated violently. Very long stopping distance even at 20MPH. I had the vehicle towed to the dealership from which I had purchased it. I bought this vehicle on 25 Nov 2024. Right now its mileage is 3757. Obviously my safety and that of others was put at risk. The service department at the dealership has not communicated with me at this time. There was NO prior warning nor were there any prior symptoms of this problem. It occurred VERY suddenly.

When accelerating, the engine revved up, switched itself from drive to park, resulting in complete loss of control and the vehicle coming to a sudden stop. The car behind narrowly avoided a rear-end collision by swerving around me. The malfunction indicator light came on for the first time, and the vehicle would not switch out of park. After turning the ignition off and on again, the vehicle would switch out of park. The GMC service inspector ran diagnostics and found fault codes related to the transmission valve components that must be replaced.

The contact owns a 2024 GMC Terrain. The contact stated that while the vehicle was parked, the check engine warning light illuminated. The contact stated that while driving at an undisclosed speed and merging onto the highway, the vehicle experienced a loss of automotive power. The vehicle was taken to a local dealer where the vehicle was diagnosed. The contact was informed that an undisclosed faulty sensor was the cause of the failure. The contact was informed that the sensor needed to be replaced. The contact stated that the vehicle had remained at the dealer for two weeks unrepaired. The manufacturer was not notified of the failure. The approximate failure mileage was 22,000.