2018 GMC TERRAIN Complaints

View complaints related to 2018 GMC TERRAIN. The complaints found here are submitted by actual consumers with first hand experience. There are more than 220 complaints submitted for the 2018 GMC TERRAIN. You can submit your own complaint to the NHTSA or call the Hotline, Monday-Friday 8am to 8pm at (888) 327-4236, TTY: (800) 424-9153.

  • 2018 GMC TERRAIN
    - rio grande city, TX

    While driving truck around 55mph with family in vehicle and tried to make a stop in a traffic light, notice truck had a hard brake pedal and did not stop, luckily I (Parent) around [XXX] of age was able to divert around and put on neutral until truck stoped in side of road. After a while of looking around and checking truck for system errors or lights there was no indication not warnings. i was able to move truck to a near by location and asked a mechanic to go look at it. Mechanic notice oil coming out of brake vacuum pump and took out part and mentioned that the pump had broken in pieces inside engine block and might need a replacement. Truck is still on shop and waiting for our decision to fix. At this point my family is so scared of this truck and don't even want to talk about the incident. Me as a parent is very concern on all this new vehicles that are suppose to be more reliable and better protection than older vehicles , i feel more protected in my 90’s truck. I hope this gets enough attention to at least save someone's life. Thanks in advance, [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

    Source: NHTSA WEB SITE
  • 2018 GMC TERRAIN
    - Ontario, CA

    While driving the vehicle which only has 68,000 miles the reduced engine power warning light appeared. As quickly as was safe the car was pulled to the shoulder. It was towed to the dealer who states the Vacuum pump seized causing the camshaft phase actuator locating pin to spin. Originally they stated a new camshaft and vacuum pump were needed at $3,500, but now state the entire engine is damaged and must be replaced at cost of $12,000. The vehicle was well serviced and this manufacturing flaw lead to the vehicle be stopped on the road putting both the occupants and others around at risk.

    Source: NHTSA WEB SITE
  • 2018 GMC TERRAIN
    - Benton, AR

    I was driving and my brakes seized up. Could not apply pressure at all. This could have caused serious injury to myself and my daughter as we were driving alone 3 hours from home. I was able to get into a parking lot but now my car won't start.

    Source: NHTSA WEB SITE
  • 2018 GMC TERRAIN
    - Willits, CA

    Rear side windows in hatch area leaked filled up spare tire compartment with about 3-4 gallons of water. Now navigation doesn't want to work, sunroof not working, electric systems are not working right

    Source: NHTSA WEB SITE
  • 2018 GMC TERRAIN
    - Cleveland, TN

    My vehicle keeps showing “service brake assist” and “service TSC” lights. I was on a hill and the auto-start was engaged, as well as hill assist. When I let off the brake pedal slightly to get the car to come out of auto-start, the car acted like it completely shut off (radio went black and lost power) and the car just started rolling backwards quickly. If there was a vehicle behind me it would’ve %100 caused an accident. My wife and child ride in this car every day and this is the second time I’ve had serious issues with this car. The first time I was driving down the interstate and the brake vaccuum pump went out and I lost all brakes, I had to put all 180lbs of my weight on the brake pedal to get it to stop.

    Source: NHTSA WEB SITE
  • 2018 GMC TERRAIN
    - Epsom, NH

    Vehicle brakes went completely hard and vehicle would not stop. There was no warning signs, no lights on the dash and vehicle was driving on highway normally. Upon taking a highway exit, I could not stop the vehicle, completely unexpectedly. Upon further research it is a very common problem that needs to be addressed. My 3 kids and wife were in the vehicle when it happened, and this is actually the second time it has happened. The first time it happened we could not stop the vehicle at all to turn onto the road I live on, could barely push the brake pedal and coast to a stop. The repair last time it happened was the camshaft driven brake booster vacuum pump, and it has failed again after 20,000 miles. This is a serious manufacturer defect that has almost killed my family twice now.

    Source: NHTSA WEB SITE
  • 2018 GMC TERRAIN
    - Columbus , OH

    The door locks began to have issues; the locks started to work only occassionally for no apparent reason. I've been locked out of the car several times and had to use the auxiliary key. Plus I couldn't lock the car while I was inside as the interior door lock button wouldn't lock or unlock the doors either. It's not a kefob or battery issue and no lights on the dashboard. The dealer reports that they couldn't reproduce the issue. However they found corrision on the electrical harness inside the passenger front door. I replaced an electrical harness in the rear bumper 18 months prior for corrision found. The dealer says they received a service bulletin on the "electrical harness" issue however the dealer won't cover the cost of $500 to replace the harness. As this deals with the electrical system, my concern is that it may effect the operation of other components of the car while it's running. Safety and security is of the utmost importance whether at home or away as it regards to being able to lock or unlock the doors.

    Source: NHTSA WEB SITE
  • 2018 GMC TERRAIN
    - Anchor Point, AK

    This complaint is for the rear camera / back up camera system: After purchasing the vehicle the back up camera started to get hazy around 25,000 miles. At 35,000 miles it was completely useless. I purchased a second back up camera and had the body shop install it. It has now been right at the same mileage, 30,000 miles, and the camera is again hazy. This is not an external haze where I can just wipe the camera off, even carefully so as to not scratch the lens or cover, but a haze that is behind (inside) the protective outer lens (cap). This has happened with both cameras and I am facing installing a third. My vehicle has less than 70,000 miles on it! I've had other vehicles where the camera lasted way longer (lifetime!) of the vehicle. When I went to the dealer with the complaint on the original equipment they said it was because the lens was scratched, but didn't look any further that the lens was foggy 'inside'. The safety of myself and others comes into play when I cannot see what is behind me: trees, curbs, vehicles, people, drop-offs. Also, at night when in reverse the dash area the feed goes to is so bright that it blinds the driver and the system is unable to be dimmed to allow proper viewing.

    Source: NHTSA WEB SITE
  • 2018 GMC TERRAIN
    - Villa Grove, IL

    Head on collision with a deer destroying the front head light and severely damaging the drivers side door. No airbags were deployed.

    Source: NHTSA WEB SITE
  • 2018 GMC TERRAIN
    - Detroit, MI

    I was driving my car December 10, 2023 when I was at a red light my truck completely shut down I could not reverse I could not put in drive I could not put in Park I could not switch gears. I didn’t know what happened. I had to call a tow truck to get me home once I got home I got my car towed to a shop. Before my car was towed I contacted OnStar. OnStar did a diagnosis on my car and it came back ECM which stands for electric control module. When my car was at the shop i got a tune up & the mechanic was able to start my car. Driving again on the date of December 15, 2023 it did it again and it said ECM. I was paranoid because I was on the expressway I had too get my car towed to the Dealership. This is the second time that my car has did this. I keep all maintenance up on my car. I’m not understanding what’s going on. I feel like it should be a recall on this issue. It was very dangerous both times that my car stopped. Now yet again I’m waiting to see what the problem is. This is definitely a safety recall issue. I have a 2018 Denali terrain with only 71,000 miles i keep up with oil changes and maintenance on my vehicle. Who do i contact about this concerning scary situation, Will it take for a person to die before this is is rectified. Someone please contact me or respond to this situation. So we can request for a recall on this serious matter

    Source: NHTSA WEB SITE