GMC Terrain Complaints (2018)

226 consumer complaints on file.

#11673291July 14, 2025
SERVICE BRAKES, ELECTRICAL SYSTEM, UNKNOWN OR OTHER
Component Affected: Service Brakes, Hydraulic – Brake Vacuum Pump Summary of the Problem: I am reporting a serious safety issue involving the brake vacuum pump on my 2018 GMC Terrain. The brake pump failed catastrophically ("blew up"), resulting in a sudden loss of braking power. This occurred without warning and posed a significant risk to my safety and others on the road. We were traveling to vacation in Florida and thankfully had just gotten off the interstate. Details: The failure caused the brake pedal to become extremely hard to press, and the vehicle required a much longer distance to stop. We experienced no brake at the brake booster and a blown vacuum pump is due to a faulty vacuum pump which is a known issue for this model. Fortunately, no accident occurred, but the situation could have easily led to a collision. A certified mechanic confirmed that the brake vacuum pump exploded and needs to be replaced. I have incurred significant out-of-pocket repair costs due to this issue. We had to uber to our vacation room, get Walmart Plus to have groceries delivered to our room. We had to have Uber Eats deliver other supplies. We have had to walk to various places for dinner and entertainment because Avis and Budget had no vehicles available to rent and Enterprise was closed as we arrived on Saturday afternoon. I have checked for recalls and service bulletins using my VIN, but none are currently listed for this specific issue, despite similar problems being reported in other GM vehicles. Request: I urge the NHTSA to investigate this issue further. The failure of a critical braking component without warning is a serious safety concern. I believe this may be part of a broader pattern of brake system failures in GM vehicles and should be addressed through a recall or safety campaign. Also, the estimate for the repair is $2,500 so any reimbursement would be greatly appreciated. We just received this estimate but I can provide it at a later date.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11672277July 9, 2025
ENGINE
Broken piston land and ring. car went into 'limp mode' while driving on interstate. Taken to dealer, told new engine was needed.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11667521June 17, 2025
ENGINE, SERVICE BRAKES
My car started experiencing a strange problem while braking on June 15. I released the parking brake leaving my parents driveway. I coasted backwards (as usual), and when I pressed the brake the car didn't stop as expected and the brake pedal was very hard to press. It eventually stopped. I put into park, then put the emergency brake on, then released all and tried again and encountered the same issue, that it was very very slow to stop and the brake pedal was hard to push in. I got home, parked the car - tested the reverse brake on flat surface and didn't notice the issue. The next day, the problem started happening with the front brake as well and an error code popped up that said 'check brake assist' which I've never seen before. I brought it to my local mechanic, who took a look and said that it's a vacuum pump failure, and the result is a lot of metal shards were released into the engine when the vacuum pump failed. My mechanic recommended I take to a GMC dealer for further evaluation. I looked up the recall on this issue, and see that it impacts a lot cars, including the 2017 GMC terrain, but not my 2018 GMC terrain. I am going to take it to the GMC dealer but I'm afraid I won't be able to afford the repair, and it doesn't seem like there was anything I could have done to prevent this from happening.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11662829May 23, 2025
AIR BAGS, SEAT BELTS
The contact owned a 2018 GMC Terrain. The contact stated that while driving and nearly coming to a complete stop in the right lane, another vehicle driving approximately 40-50 MPH crashed into the rear of the vehicle, causing the contact to hit her face against the steering wheel, and the contact became unconscious temporarily. The contact stated that upon regaining consciousness, the contact noticed that the vehicle had moved to the grass by the left lane of the road, where traffic was going in the opposite direction. It was unknown whether the vehicle was involved in a second collision. A message advising that an accident was detected and inquiring whether 911 should be contacted was displayed. The contact stated that the air bags failed to deploy, and the front driver's side seat belt failed to retract as needed. A bystander opened the driver's side door to verify that the contact was safe. The contact noticed that she was bleeding significantly and was unable to move the right shoulder and the neck. The emergency units assisted the contact out of the vehicle. The emergency units placed braces on the contact's neck and placed the contact on a stretcher. The contact was transported to the hospital, where the contact underwent X-rays and CT scans. The contact was informed that she had sustained a concussion, lumbar injuries, a fractured nose, loss of taste and smell, laceration on the inner and outer side of the bottom lip, carpal tunnel on the right hand, severe whiplash, laceration on the right shoulder, and a cut behind the right ear. The contact was in the process of undergoing MRIs. A police report was filed. The vehicle was towed and totaled, but was still under investigation. The dealer was not notified of the failure. The manufacturer was notified of the failure, and a case was filed; however, no further assistance was provided. The failure mileage was unknown.
Crash:
Yes
Fire:
No
Injuries:
1
Deaths:
0
#11659131May 5, 2025
ENGINE, POWER TRAIN
Timing chain. It had no warning and failed due to poor design and gm in Europe fixed/addressed the issue by installing a plate behind the tensioner a part that isn’t available in the us.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11655816April 21, 2025
SERVICE BRAKES
Brake booster went out and lost all braking ability on interstate doing 65 mph in spring of 2022 - had brake booster and exhaust cam replaced and April 20 2025 same break and same effect - no braking ability at interstate speed - extremely dangerous situation
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11655132April 17, 2025
ENGINE
My vehicle’s engine was the component that failed. I was driving home from work. It is a forty-two minute commute. I was five minutes away from home when the vehicle slowed down in speed to a cruise. There were no issues prior after startup. There were no strange sounds, no start up issues, and no lights on the dashboard at all. I noticed that the vehicle had put itself into neutral gear. When I tried to stop the vehicle by hitting the break, the break did not work. I put my foot on the gas pedal and the car did not speed up. I could not change the gears. There was nothing I could do. The vehicle came to a complete stop when it powered off. When the car was put into accessory mode, there was an error message that stated the engine/vehicle was in low power mode. I was not able to start the car’s engine again. It was useless. The only way to move the car anywhere was to have it towed. This failure was scary and dangerous because it occurred in the middle of the night on a main road. Cars are known to drive above the speed limit past midnight in this area. I was glad that there were no cars on the road at the time. I was not aware of this failure occurring for my vehicle no were there any other known recalls. After doing some personal research, I found that GMC and certain Chevy models are having this problem, but no source listed any GMC Terrains as affected vehicles; although the same thing that happened to other people happened to me. I purchased an extended warranty through Fidelity Warranty Services, Inc. (Platinum) when I purchased the vehicle. They were the ones that had done all the necessary inspections for the filed claim once the vehicle was taken to a GMC Service center: Anderson Buick in Cockeysville, MD.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11649862March 22, 2025
UNKNOWN OR OTHER
I was 30 seconds away to pull in my driveway. WARNING came up on screen (service) TRANSMISSION UNABLE TO SHIFT. When I turned into my driveway the vehicle stopped suddenly & threw itself into PARK. Vehicle still running but would not go into any gear, drive or reverse. I then pushed the PARK button & I think it said EMERGENCY BRAKE RELEASED. I then proceeded to drive up my driveway with no problem. Haven’t gotten back in vehicle yet as I am afraid to but l made appointment to take it to the dealership to check it out. On 3/24. (Linus Cadillac Buick GMC)Thank god it happened in my driveway as it would’ve caused an accident. ( the vehicle was driven up the Rd. walking distance. Sat there for an hr. Visiting my family. Then was driving home When incident happened. So it wasn’t running hot or anything.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11644047February 21, 2025
POWER TRAIN, FUEL/PROPULSION SYSTEM, ENGINE
My check engine light comes on intermittently, since March 2024, after having Cabin & Engine air filters replaced. Each time, I’m told it is code P0171. This has happened too many times for my comfort. Usually, it happens around the time my gas gets below 1/2 tank or after I fill up my gas tank. Originally, I was told by the mechanic that it could be one of four things, of which I’ve now had some of things done. InIn Aug. 2024, the check engine light came in. Code was P0171. Mechanic replaced the Brake vacuum pump. Once incident, almost a month later, on 9/24/24, was very scary. While driving on the interstate, I got ready to increase my speed, but heard a pop sound and noticed the speed wouldn’t accelerate. Next, the check engine light came on and the message in the dash popped up saying “engine power reduced” or something similar. I was able to coast from the fast lane over to the slower lane and off the highway into a parking lot. I turned the truck off. When I crunk it back up an hour later, it was shaking and jerking. While slowly driving, on the way to the mechanic shop, it jerked and shook each time I tried to accelerate after stopping at a light or slowing down with traffic. The code again was P0171. According to the mechanic, the intake hose had popped off. On 11/13/24, the check engine light came on. I again took it to have the code scanned and truck looked at. Test results again showed P0171. This time the Mass Air Flow Sensor was suggested. In a year I’ve had the fuel system cleaned twice, brake system flushed, & other routine maintenance such as oil change & brakes. Yet, my check engine light seems to still come on intermittently atleast once monthly. It came on two days ago, 2/18/25, when my gas was around 1/4 tank full. I added a fuel system injector, per mechanic suggestion, and filled my tank up with gas on today, 2/20/25. The check engine light had gone off within about 15 mins of me driving. I’m certain it will be back on soon with the same code.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11643291February 18, 2025
ENGINE, SERVICE BRAKES
Brake vacuum pump failed causing engine damage. Camshaft on national back order. Vehicle has been in repair shop for 1.5 months waiting on part. No ETA. There has been recall for similar vehicles with same issue, failure, damage. But not for this VIN. It’s the same failure with same damage. How is this not a recall for this VIN?
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11640299February 3, 2025
SERVICE BRAKES, HYDRAULIC
The contact owns a 2018 GMC Terrain. The contact stated while driving at various speeds, the vehicle would not decelerate as intended while depressing the brake pedal. No warning light was illuminated. The vehicle was previously repaired at a local independent mechanic and the vacuum pump was replaced; however, approximately 32 days later the failure reoccurred. The local dealer was not contacted. The manufacturer was not made aware of the failure. The failure mileage was approximately 58,000.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11638594January 26, 2025
UNKNOWN OR OTHER
My car is allowing me to drive without the key fob. I've drove two hours away from my house where my key fob was. It allows me to shut off the vehicle. Vehicle says ' no remote detected. Press Brake to restart. This is the 3rd incident. This is definitely a safty issue. Someone can take my car 2 hours or so from my residence.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11638157January 23, 2025
SERVICE BRAKES
I was slowing down to turn and I couldn't push my brake pedal down it completely locked up. If I wasn't already slowing down I would've hit a power pole and potentially lost my life. My ABS light never came on and it's still not on. After I got parked and shut my car off the check engine light came on.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11633346December 31, 2024
SERVICE BRAKES
Faulty Brake Vacuum Pump triggered my brake to get stuck while I was driving ended on the side of the express way to avoid traffic and prevent a crash.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11633068December 30, 2024
SERVICE BRAKES, ENGINE
I got my car out of the shop a week ago for my brakes the car was in the shop for a month and this past weekend my car is doing the same exact thing a week later I was on I 75 also hit a semi truck
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11633081December 30, 2024
ENGINE, SERVICE BRAKES, HYDRAULIC
The contact owns a 2018 GMC Terrain. The contact stated while driving 40-45 MPH, the vehicle started coasting and stopped unintendedly. The contact stated that the vehicle drove for a while and then coasted and stopped. The message that the “Engine Power Reduced” was displayed. The contact stated that the brake system warning light was also illuminated. The vehicle was towed to an independent mechanic who determined that the camshaft had disintegrated into the engine. The mechanic informed the contact the vehicle was unrepairable. The vehicle was not repaired. The local dealer was not contacted. The manufacturer was not made aware of the issue. The failure mileage was approximately 60,000.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11632952December 29, 2024
STRUCTURE:BODY
The strike plate on my rear driver door fell off. The plate and bolts are in perfect condition but the backing is gone. Multiple body shops have attempted to locate the backing, which is somewhere between the interior and exterior metal body pieces, and gave been unable to. Every body shop I've taken it to also says that they have never seen anything like this happen before. They are reluctant to fix it because that would mean cutting through the body to replace the backing for the strike plate then welding, sanding, and painting in the area they cut and they worry about the integrity of the striker and functionality of it as well, as they've never had to do a repair like this before. One of the body shops was also a certified GM repair shop at the dealership from which the car was purchased and even they have said the same as the others. They also encouraged me to report this to the NHTSA and GM as well because they've never seen it happen or heard of it happening and they are concerned because it is a safety issue. I know that there is a similar recall on some newer GMC Terrains and wonder if my issue would be related to the recall or if it's is a separate issue all together. The striker was barely touched and someone exited my back seat and fell off into a parking lot, I was able to recover the striker and both bolts which are completely undamaged and unworn. This is my only vehicle so I now have to hold my door shut with bungee cords and tape in order to use my vehicle. I have a child who is still in a car seat and must remain in the back seat for safety but now my backseat is also not very safe because of the door. A few days prior to the striker falling off my door would not close fully flush with the rest of the vehicle but still closed, locked, and remained closed with no other issues.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11631046December 16, 2024
ENGINE AND ENGINE COOLING, FUEL SYSTEM, DIESEL
The contact owns a 2018 GMC Terrain. The contact stated while driving at approximately 65 MPH, the check engine warning light illuminated, and the vehicle decelerated to 20 MPH. Additionally, the message "Service Emissions" was displayed. The vehicle was taken to the local dealer who diagnosed that the diesel particulate filter was faulty and needed to be replaced. The vehicle was not yet repaired. The manufacturer was notified of the failure, but no assistance was offered. The contact was informed that the VIN was not included in the Extended Warranty coverage for the repair. The failure mileage was 26,000.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11630230December 11, 2024
SERVICE BRAKES
I have a 2018 Terrain SLT. On 11/20/24, I was headed home from my commute to work driving my terrain with all the confidence in the world because I hadn't had any major issue with it. In 5pm stop and go traffic I decided on another route to my son's school to pick him up from practice. As the light at the end of the bridge turned red, I proceeded to stop, and my brake pedal was as stiff as stone. Going across that bridge I was literally standing up on the brake pedal with my back and shoulder against the roof of the truck for support trying to stop. As I came close to the cars that had already stopped I contemplated jumping out of the car but I decided to keep at it. It was God and God alone that cleared a shoulder for me to be able to pull over. I was petrified!! No signs, no brake noises, no hesitations, nothing! No warning lights on the dash, no alerts, NOTHING! Brakes were just gone! The mechanic said the vacuum pump had exploded and it was a known issue with terrains and that there was a bulletin regarding this. Pieces of the metal from the exploded vacuum pump were found inside of the engine. The mechanic was upset about the event and said to notify GM, something needed to be done about it. He gave me the vacuum pump to show the GM service center and he said one of the mechanics took pics of the metal in the engine. I called GM and was told to bring it in to a GM service shop so that they could check it out, but at my expense because the manufacturer warranty had expired. I AM SO UPSET WITH GM!! I have anxiety every time I go to press the brake! Panic attacks thinking about the possibility of this happening with my kids/elderly parents in tow. Thank God for covering me and all the drivers and their families that could have been hurt. Thank God my son/elderly parents weren't in the car! The fact that this is a known issue and it hasn't been addressed is heartbreaking. GM should do the right thing and recall these trucks, asap.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11628389December 2, 2024
SERVICE BRAKES
The vacuum pump exploded and I lost power braking ability while going approx. 40mph. If I hadn't pressed down hard on the brakes to slow down, in less than 2 minutes I would have ended up in Lake Michigan, as I was heading east toward the on ramp for [XXX]. The problem has been confirmed by European US Auto here in Chicago, and I have photos. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0

← Back to GMC Terrain