What 212 owners told NHTSA about the 2018 GMC Terrain

Vacuum pump that supplies vacuum to brake booster failed without any warnings beforehand leaving us without the ability to stop. Luckily was able to avoid an accident.

NHTSA ODI 11742410

While traveling on the highway in traffic, brakes became very stiff when depressed after attempting to slow down to exit. Was able to put full bodyweight into the brake pedal to slow enough to exit and navigate to the gas station right off the exit. Had to roll stop signs and unsafely navigate traffic because brakes were not working. Service Brake System warning light came on after the incident.

NHTSA ODI 11739875

Gas leaking from the hood. High pressure fuel pump

NHTSA ODI 11739681

The contact owns a 2018 GMC Terrain Denali. The contact stated while the contact's daughter was driving, the brake pedal was depressed, however the vehicle failed to stop as intended. In addition, the contact stated that the brake pedal was unusually hard when depressed. The vehicle was taken to the dealer where the vehicle was purchased. The contact stated that the service brake vacuum pump failed while the vehicle was at the dealer. The vehicle was diagnosed with a failed service brake vacuum pump and a failed engine. The contact was informed that the service brake vacuum pump, the CAM Shaft and the engine needed to be replaced. The vehicle was repaired. The contact stated that the failure was a known failure of the vehicle. The manufacturer was not made aware of the failure. The failure mileage was approximately 260,000.

NHTSA ODI 11737294

We just got off the bus thruway and my brakes pedal got hard to press and it was hard to stop car I had to push on brake dry hard to get the car to stop it was jarring and o had to get my some and o to a safe place. Garage said it’s brake assist and he researched there’s is an active law suit against GM bc lots of Moses and models have this issue although they claim to know nothing about it

NHTSA ODI 11726554

My car was t-boned on the driver side and no airbags deployed. The outer door and window exploded with the force. We were also hit from behind

NHTSA ODI 11724819

The control knob that controls AWD, 2WD,Off-road, and 4 x4 AWD. Just stopped working. Stuck on 2WD mode. I did have it checked for any codes, even though, there is NO check engine light is on.

NHTSA ODI 11722587

The contact owns a 2018 GMC Terrain. While attempting to shift to reverse(R) out of a parking spot, the message “Transmission Unable to Shift” was displayed on the instrument panel, and the transmission was unable to shift into reverse(R). The contact called for tow truck assistance. The vehicle was unable to shift into neutral (N). The contact stated that prior to the transmission failure, the “Service Transmission Soon” message was displayed. The vehicle was towed to a local dealer to be diagnosed, and it was determined that the transmission had failed and needed to be replaced. The vehicle was not repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 245,000.

NHTSA ODI 11721631

Faulty Brake Vacuum Pump!!!! 2018 GMC Terrain @ 119254 miles--- NO warning! Brakes were hard to press, did not work and I rolled into ditch to prevent an accident. I see hundreds of people with same issue now that I Am having to research. This was very scary. I was told it was as a brake booster pressure sensor. But that was not the problem. It is the brake vacuum pump. This is so dangerous. Why is GMC not correcting this issue? This is insane. GM issued multiple technical service bulletins on vacuum and booster issues starting in 2017. Why hasn't anything been done?

NHTSA ODI 11721477

Vehicle will not shift out of park, despite replacing the valve body, putting in a new battery, and transmission fluid. It has been this way since mid January. The codes don’t make sense and there is no current recall, nor have we had this vehicle for very long. It has 48,000 miles on it and is having this issue. Very disappointed.

NHTSA ODI 11720574

Brakes were hard to engage or press when stopping due to Vacuum pump stop working. Had to replace the vacuum pump

NHTSA ODI 11719833

The contact owns a 2018 GMC Terrain. The contact stated that while driving at various speeds, there was an abnormal grinding sound coming from the vehicle while transitioning to 4WD. The contact continued driving and the driving sound became more frequent while shifting into 4WD. Upon inspecting the vehicle, the contact discovered that the driveshaft had detached and was hanging down from the suspension. An independent mechanic was contacted, and the contact was informed about NHTSA Campaign Number: 17V516000 (Power Train); which the mechanic associated to the failure. The contact called two local dealers and was informed that the VIN was not included in the recall. The manufacturer was notified of the failure, and the contact was referred to the NHTSA Hotline to report the failure. The vehicle was not repaired. The failure mileage was approximately 160,000.

NHTSA ODI 11716669

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.

NHTSA ODI 11714113

Vacuum pump failure resulting in crankshaft sensor to completely sheer off.

NHTSA ODI 11708515

The infotainment system will just randomly start going haywire and when it happens, you cannot use the touchscreen. It will try to randomly delete app icons such as the camera, it will try to delete connected phones, it will try to delete radio favorites and it will move app icons all around. These are just a few examples of things that happen.

NHTSA ODI 11704389

The contact owns a 2018 GMC Terrain. The contact stated that while driving approximately 30 MPH, the brake pedal became extremely difficult to depress, with the message "Brake Assist" displayed. The vehicle was driven to the shoulder of the roadway and the parking brake was activated, and the vehicle was turned off. The contact stated that the transmission failed to shift into gear, and the vehicle was dragged onto a flatbed truck and towed to the residence. The cause of the failure was not yet determined. The local dealer and manufacturer were notified of the failure, but no assistance was offered. The failure mileage was 132,386.

NHTSA ODI 11703650

The contact owns a 2018 GMC Terrain. The contact stated that while driving at an undisclosed speed, the vehicle shuddered and failed to come to a stop while the brake pedal was depressed. The check engine warning light was illuminated. The vehicle was taken to a local independent mechanic, where it was diagnosed with a locked brake vacuum pump. The contact was informed that parts of the brake vacuum pump had entered inside the camshaft and valve cover. Several unknown local dealers were contacted. The vehicle was not diagnosed or repaired because there was no recall associated with the VIN. The manufacturer was made aware of the failure. The failure mileage was approximately 183,000.

NHTSA ODI 11700844

The contact owns a 2018 GMC Terrain. The contact stated that the transmission was shifting gear erratically. The contact stated that the doors were locking and unlocking independently, and the instrument cluster was blank. There was an abnormal beeping sound coming from the vehicle. Additionally, the contact stated that while at a traffic light, the Auto START/STOP feature delayed to respond. OnStar was alerted, but the contact declined to perform the service. The contact was in contact with the independent mechanic who sold the vehicle, but no assistance was provided. The local dealer was contacted. The vehicle was not diagnosed or repaired. The manufacturer was contacted, but no assistance was provided. The failure mileage was approximately 130,000. The VIN was not available.

NHTSA ODI 11698239

My car said to me this not that there is something wrong with the Service Safety Restraint system! It was fine last night when I got home! I just bought this car a month ago and everything was fine and now my air bag light is on and will not go off!

NHTSA ODI 11696252

The contact owns a 2018 GMC Terrain. The contact stated while driving at an undisclosed speed, the air bag and ABS warning lights illuminated. The vehicle was taken to Auto Zone to be diagnosed. The vehicle was diagnosed with air bag failure. The contact was informed that the air bag needed to be replaced. The vehicle was not repaired. The dealer was made aware of the failure; however, the contact was informed that there were no open recalls on the VIN. In addition, the contact was informed that once a recall repair was completed, it would not be performed a second time free of charge. The manufacturer was not made aware of the failure. The failure mileage was approximately 95,100.

NHTSA ODI 11694159

The contact owns a 2018 GMC Terrain. The contact stated that while driving at an undisclosed speed, the unintendedly decelerated and failed to properly accelerate. The vehicle was taken to the local dealer, who diagnosed the vehicle with transmission failure. The contact was informed that the transmission needed to be replaced. The transmission was replaced with a used transmission, but the failure reoccurred. The vehicle was taken back to the local dealer who diagnosed and determined that the replacement transmission had failed and needed to be replaced. The vehicle was not yet repaired. The manufacturer was not notified of the failure. The failure mileage was 53,000. The VIN was not available.

NHTSA ODI 11692086

April 2025, Vacuum Pump went out meaning lost breaks going 60 miles per hour down the road after engine light came on. Left me and two children stranded 2 hours from home with no way to get back except a tow. Now September 2025 Cam Shafts are out as well as Vacuum Pump. Stranded boyfriend and I two hours away again. Now metal in oil and warranty is not willing to cover it due to the vacuum pump going out. Made a post on Facebook and got lots of feedback on how their newer terrains have done the same things. Work in insurance and have people car pertaining to their terrains wondering if we cover engine replacements. There is major issues with these vehicle. Mine only has 107,000 miles on it and I have 12,000 left to pay. The motor is shot and dealership wants to “flush” the metal out of the engine. Very frustrated, I put 12,000 out of my college fund to have a reliable vehicle for my two kids and now this is all I have. A car that doesn’t run. I called warranty and the man I talked to even said that they get a lot of calls for these cars needing to be fixed. I am at a loss on what to do now. The below information about the incident is for the most recent one happening in September. I know that this sounds like a warranty and dealership issue but I guaranty if you send something out to terrain owners they will report major issues that they have had. Leaving them stuck in loans and no where to go.

NHTSA ODI 11691195

The contact owns a 2018 GMC Terrain. The contact stated that on several occasions while driving at various speeds, the infotainment system screen and radio inadvertently switched stations from AM to FM. On other occasions, while driving and using the GPS system, the screen went blank. The contact stated that on several occasions the screen was turned off, and on other occasions, the screen was turned off and on however, the failure was temporally fixed. The vehicle was not diagnosed of repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 77,000.

NHTSA ODI 11683657

It starts to “warn” you by the seat doing whatever it does and the dash lights up collision flashing and slams on the brakes when nothing is even around

NHTSA ODI 11682338

I bought this car used and had only had it about a month when I was driving to work and was in slow traffic on the freeway when my car slowed to a stop despite the fact that I had my foot on the gas pedal. It turns out it was a transmission failure. My safety and the safety of the drivers around me were put at risk because I was unable to move my car over to the shoulder and out of the lane of traffic. Traffic was slow but was still moving. My vehicle is available for inspection but I’ve already had it repaired so I no longer have the faulty transmission. The problem was confirmed by an independent service center where I had it repaired. The vehicle was inspected by the dealer and the independent service center. The dealer had it for 12 days but was unable to diagnose it so I took it to an independent service center. It was also briefly looked at and listened to by the highway patrol officer who assisted me and he also thought that the transmission had failed. The check engine light was on when this incident occurred but I was having an issue with one of the glow plugs and I thought that that was the reason. The check engine light came on the night before the transmission failed.

NHTSA ODI 11678945