2026 GMC Terrain Owner Complaints

On the evening ofXXX, at approximately 6:00 PM, I was driving this Avis rental vehicle on a highway in [XXX] at normal highway speed, below the posted limit, with my foot on the accelerator. The forward collision warning and automatic emergency braking system activated and applied the brakes hard. There was no vehicle, pedestrian, obstacle, or hazard ahead of me, and no vehicle behind me or beside me. The roadway was clear and dry. The sun was low in the sky, and the vehicle was crossing a metal expansion joint on an overpass at the moment of activation. I believe the low sun angle, the expansion joint, or both caused a false object detection by the forward-facing camera or radar. The service brakes themselves functioned correctly. The failure is in the forward sensing and decision logic, which commanded a braking event with no object present. The deceleration was severe and unexpected. I sustained sharp pain in my neck and shoulder. Had any vehicle been following me, this would have caused a rear-end collision at highway speed. There were no warning lamps, messages, or other symptoms before the event, and none afterward. I had driven the vehicle for seven days with no prior indication of a fault. I exited the highway immediately and drove back to the rental location on local streets at low speed because I no longer trusted the vehicle. I returned it the following morning when the Avis office opened, more than a day early, and reported the defect. Being a rental vehicle it was not available to me for inspection. The rental company has advised that it was taken out of fleet for inspection after my return, that there are no open recalls on it, and that it will not release internal service records to me. I do not know the outcome of that inspection. To my knowledge the fault has not been reproduced or confirmed by a dealer, independent service center, or manufacturer representative. No police report was filed because no collision occurred. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S

NHTSA ID

11766350

Incident

Aug 29, 2026

a failing telematics module on your 2026 GMC Terrain is causing network corruption, leading to an erratic speedometer and loss of driver assistance systems while driving.

NHTSA ID

11765984

Incident

Sep 18, 2026

My vehicle is making a squeaky sound/noise when breaking and getting louder. I took it in for service and they couldn’t seem to find the issue. It’s coming from the front end of the vehicle

NHTSA ID

11765446

Incident

Jul 10, 2026

Shimmy, shake, wobble, after TSB 26-NA-109 repair, replace front springs, vehicle feels less stable at highway speeds. The initial condition, Shimmy, Shake, Wobble, under moderate acceleration, still exists after last repair attempt.

NHTSA ID

11765270

Incident

May 19, 2026

The contact owns a 2026 GMC Terrain. The contact stated that while driving 10 MPH and pulling into a parking lot, the vehicle was shifted into drive(D) and the driver’s door lock unexpectedly unlocked. The contact stated that on another occasion, a passenger in the front passenger’s seat noticed the same failure with the passenger’s side door lock. The vehicle was taken to the dealer, where it was not diagnosed or repaired. The contact expressed concern that the failure was hazardous and posed a safety risk because the doors could open while the vehicle was moving. The manufacturer was not made aware of the failure. The failure mileage was approximately 2,500.

NHTSA ID

11764146

Incident

Sep 12, 2026

Mileage

2,500 mi

Avis Rental. Vehicle simply shut down while driving and would not re-start. Vehicle could NOT be put into neutral to move from roadway. Emergency services vehicles had to remain on site awaiting tow vehicle. Very dangerous situation.

NHTSA ID

11763641

Incident

Sep 11, 2026

I recently pulled over to help a woman driving a 2026 GMC Terrain who had run out of gas in the middle of XXX in Virginia. Obviously, the first priority was to get the vehicle out of the travel lanes and onto the shoulder. I tried to figure out how to put the Terrain into neutral so we could move it, only to discover that **the vehicle cannot be shifted into neutral if it is not running.** Since it was out of gas, it could not start, meaning we could not put it in neutral and could not move it out of the roadway. Fortunately, a VDOT Safety Service Patrol truck came by. The driver stopped to help and thankfully had gasoline. However, I was told that, according to policy, he could not put gas in the vehicle while it was still in the travel lanes. This created an extremely dangerous catch-22: **the vehicle could not be moved because it could not start, it could not start because it was out of gas, and gas could not be added because it had not been moved out of the roadway.** I believe this is a serious safety issue with the vehicle. A disabled vehicle should have a reliable way to be placed in neutral regardless of whether the engine can start. This is especially important after a breakdown or crash, when the vehicle may need to be moved quickly to protect the occupants, other drivers, or first responders. If there is a manual emergency procedure for putting a completely disabled Terrain into neutral, it should be clearly documented and readily accessible to drivers and roadside assistance personnel. If there is no practical method, I believe GMC needs to address this design. A modern vehicle should not become an immovable roadblock simply because it ran out of fuel. Please investigate this issue and take whatever action is necessary to ensure disabled vehicles can be safely moved out of active traffic lanes.

NHTSA ID

11761336

Incident

Aug 27, 2026

When starting to accelerate from a red light. The car in front of us was accelerating faster. Yet our car initiated an emergency braking action at around 15 MPH. It was very jarring and I still have a headache more yhan 1 hour after the incident.

NHTSA ID

11760736

Incident

Aug 30, 2026

Subject: Urgent: Unresolved Ongoing Vehicle Issues - Request for Contact ​To Whom It May Concern, ​I am writing to express my strong frustration regarding ongoing and unresolved issues with my vehicle. Ever since I purchased it, I have been plagued by constant alerts regarding various vehicle failures. ​My vehicle has already been reset and updated twice to address these issues. I just picked it up after it was supposedly fixed at the dealership this past Thursday. However, today, Sunday, [XXX], the exact same warning alerts have started popping up once again. ​This situation is unacceptable, and I need someone to reach out to us immediately to discuss a permanent resolution. Please contact us at either of the following numbers: ​Primary Phone: [XXX] ​Secondary Phone: [XXX] ​I expect a prompt reply to arrange the next steps. ​ INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11758926

Incident

Jul 10, 2026

The contact owns a 2026 GMC Terrain. The contact stated that after a software update was performed, while driving at an undisclosed speed, the message "Departure Lane Limited due to the Trailer" was displayed. The failure affected the blind spot warning system. The warning light failed to display while approaching a vehicle on the blindside and erroneously operated while there were no vehicles on the side of the vehicle. Additionally, the "Rear Cross Traffic Warning" light was affected by the failure. The vehicle experienced hard braking while there was no other vehicle nearby. The dealer was contacted and diagnosed the vehicle with sensor failure caused by an impact to the sensor. The vehicle was not repaired. The manufacturer was made aware of the failure and referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 11,350.

NHTSA ID

11755239

Incident

Jun 25, 2026

Mileage

11,350 mi

At 12,000 miles removed old air filter found grass under air filter

NHTSA ID

11754857

Incident

Aug 3, 2026

The Screen calls my own phone number and hangs up over and over if I just ended a call. I am not able to use any part of the screen afterwards such as my map. It stays like that until I disconnect the Bluetooth and wifi from my phone while trying to drive. Safety issue!

NHTSA ID

11748887

Incident

Jun 26, 2026

This vehicle was bought new and is a NEW 2026 GMC TERRAIN DENALI with less than 5,000 miles at this time. It is a continuous event and not a specific failure date, but began soon after purchasing. The specific parts are UNKNOWN. It could be tires, wheels, steering parts (CV JOINTS, CONTROL ARMS ETC) or possibly transmission. I took it initially to the purchasing dealership and they took it for a ride and just dismissed the problem without investigating. Several days later I called and talked to the person who sold me the SUV and was told either him or service manager or both would call me, but neither did so. They were to set up a return date. After this insulting experience I decided to take it to a Cadillac dealer that I have had great experience with in the past. They took it for a ride and did experience the problem and investigated what they thought could be causing the SUV to wobble, shimmy, or shaking sensation. This Cadillac dealer said there investigation showed nothing wrong and returned the vehicle to me and said nothing could be done unless GM gave them permission. Next I wrote to the service manager expressing my disappointment in nothing being done and my disappointment in General Motors. There is a Service Bulletin (Document ID: PIT6466). This makes four efforts on my part to get satisfaction with this 2026 GMC TERRAIN DENALI and how it is not fun to drive and there is anxiety on the safety of the vehicle when being driven. *Now for the problem I am experiencing with this 2026 GMC TERRAIN DENALI. There is the sensation of a “wobble, shimmy, or shaking” under low to moderate acceleration when going straight or turning. It could be tires, wheels, steering parts or power train. It is difficult to tell. Sometimes the sensation is as if the wheels will fall off. This is an awful feeling and gives you the feeling the SUV is not safe and it is not fun to drive at all.* Why do I have to drive a brand new expensive SUV and feel unsafe and not enjoy do so?

NHTSA ID

11748269

Incident

Feb 14, 2026

The contact owned a 2026 GMC Terrain. The contact stated that while her husband was driving on a perpendicular road at an undisclosed speed, entering a highway, the driver yielded; however, a truck in the median was attempting to cross the highway during oncoming traffic, and an oncoming vehicle crashed into that vehicle, causing the truck to crash into the front of the vehicle. The front air bags deployed as intended. The contact stated that an electrical fire started under the center console, and the driver’s shirt was burned by the fire. The Fire Department was on scene and removed the contact from the vehicle; however, a fire report was not filed. An off-duty sheriff witnessed the crash and assisted in removing the contact husband from the vehicle. The driver was taken to the Emergency Room for neck, arm, and wrist injuries, bruises, burns, and scratches. The contact was unsure of how the fire was extinguished. The contact mentioned that the smoke emitting was carbon monoxide-related. The vehicle was towed to an impound lot and was deemed a total loss by the insurance provider. A police report was filed. The dealer and the manufacturer were notified of the failure, and there was a pending inspection on the vehicle. The failure mileage was approximately 6,300.

NHTSA ID

11745975

Incident

Jun 16, 2026

Mileage

6,300 mi

ABV came on. SCR alerted I needed service. On a 25 mph road I no longer could brake randomly

NHTSA ID

11745358

Incident

Jun 20, 2026

The car has always had an issue where it would just get stuck in a low gear and RPMs would go high. Does this every single day. But recently it also started acting like it was put into neutral for a few seconds and then back into drive.

NHTSA ID

11737215

Incident

Dec 1, 2025

Two issues here. First is that the car will give a danger warning when nothing is there. Sometimes goes as far as slamming on my breaks. Both in drive and reverse. Second is the lane keep assist. It’s like it is working backwards. I turned this all off because it would jerk me out of the lane and into the other lane or off to the sides of the road.

NHTSA ID

11737214

Incident

Dec 1, 2025

Car aggressively shakes and steering wheel shakes / jerks itself side to side when accelerating. Getting worse with time. GMC has it as a known issue but has been for months. Problem is getting worse the more it is driven. GMC says it is “safe”.

NHTSA ID

11737213

Incident

Dec 1, 2025

The contact owns a 2026 GMC Terrain. The contact stated that while attempting to depress the accelerator pedal after coming from a complete stop, the vehicle started wobbling. A dealer was contacted. The vehicle was taken to the dealer to be diagnosed; however, the diagnostic result was unknown. The vehicle was not repaired. The contact associated the failure with Technical Service Bulletin: PIT6466 (Shimmy, Shake or Wobble When Leaving a Stop); however, the VIN was not included in the bulletin. The manufacturer was notified of the failure and informed the contact that there was no recall for the failure, and opened a case. The failure mileage was 5,200.

NHTSA ID

11734525

Incident

Mar 15, 2026

Mileage

5,200 mi

I bought this car new from Davidson's in Rome, NY in early March 2026. This is a 2026 model. Two days after I took possession, I noticed that the spare tire well was halfway full of solid ice. The car has a severe leak through the back right side window. The dealer states it needs to be replaced. The interior frames of the car were loaded with water for many weeks as it stood on the lot. Had the dealer done a final inspection of this car prior to transferring ownership to me, as they should have and stated they did, they would have found the solid ice that surrounded the spare tire and investigated the leak and repaired it BUT they would have been required to tell me of this leak I assume...if so, I would never have bought this car. They had the car in the shop now for 3 weeks as of today, April 20th, 2026, and no word on the resolution. They did give me a loaner car for use. They have to dry the car out completely and dehumidify it as well as replace the window that leaked. The risks going forward is to the internal wiring, mechanicals, etc. due to static water exposure for many weeks prior to the sale. Had the dealer done their job with prior inspection, this could have been avoided. I asked them for my money back and they refused so I am stuck with a brand-new car that was essentially flooded with rainwater because the dealer did not do a final inspection prior to my accepting ownership of it. I wrote letter to all the dealership principals involved and NONE of them answered me directly...as if I was invisible or completely silent on this issue. If given an option, I would give them this car back and get a full refund.

NHTSA ID

11732320

Incident

Apr 20, 2026

The windshield has an optical distortion, characterized by "waviness" and "rippling." This condition is not merely a cosmetic imperfection; it is a safety hazard that causes visual impairment, and dizziness while driving. This defect compromises my ability to perceive distances and hazards accurately, especially when looking through the passenger side while making turns or looking for hazards. Current Status of the Issue as reported online Documented reports indicate that GMC dealers are aware of these "warped windshields" and that the issue appears to be a systemic quality control failure in the 2026 model year. • Safety Risk: This distortion constitutes a safety-related defect as defined by the National Highway Traffic Safety Administration (NHTSA), as it interferes with the driver's primary field of vision. •Failure of Prior Remedies: I am aware that many owners have undergone multiple replacements only to have the same defect reoccur, suggesting that current replacement stock may also be compromised

NHTSA ID

11731814

Incident

Mar 15, 2026

The contact owns a 2026 GMC Terrain. The contact stated that there was an abnormal clunking sound coming from the front driver’s side suspension while driving over bumps in the roadway, and while braking and turning the steering wheel. No warning lights were illuminated. The vehicle was taken to a local dealer, where a test drive was performed; however, the dealer was unable to determine the cause of the failure. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 14.

NHTSA ID

11731543

Incident

Jan 17, 2026

Mileage

14 mi

Car was off and parked and randomly caught on fire. Completely totaling the car

NHTSA ID

11726875

Incident

Dec 24, 2025

Purchased NEW 2026 GMC Terrain Elevation, and it came with NO User Manual. I was told by the dealership (Al Serra GMC in Grand Blanc Michigan that i could either purchase one for $50.00+ dollars, PLUS TAX & $25.00 SHIPPING, or d/l it via the infotainment system in the car, WHICH DID NOT WORK! Talk about [XXX] A VIETNAM VET!!! We are both [XXX] old & need a manual, so bought a reproduction of the original via eBay for $50.00. At least GM could reimburse the cost of the manual… INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11725669

Incident

Jan 9, 2026

Vehicle “wobble” under moderate acceleration and in corners, can be felt in the seats and steering wheel.

NHTSA ID

11724409

Incident

Jan 15, 2026