2020 GMC Terrain brakes problems

Related recalls

No recalls on file.

What owners say

1. Filed Sep 29, 2026CTBrakes

   While driving at the speed limit the vacuum pump failed on my 2020 GMC Terrain. This failure led to me enter an intersection with heavy cross traffic, nearly striking g several vehicles. This is the 3rd time I have had to replace this pump in 2 years. The pump explodes sending chards of metal into the engine leading to more damage and labor intensive work.

   NHTSA complaint #11767839 · source
2. Filed Sep 23, 2026NCBrakesEngineTransmission & Drivetrain

   While driving my 2020 GMC Terrain, I experienced a sudden loss of normal braking assistance. I had been traveling on the highway and exited onto a main road. As I approached a red traffic light at approximately 50 mph and attempted to brake, the vehicle would not stop normally. I was unable to stop for the red light and went through the intersection before I was able to safely get the vehicle off the roadway. Fortunately, there was no vehicle directly in front of me and I…

   NHTSA complaint #11766529 · source
3. Filed Aug 31, 202692,000 miORBrakes

   The contact owns a 2020 GMC Terrain. The contact stated that while driving at an undisclosed speed, the vehicle failed to stop as intended. The brake pedal was depressed to the floor, and the vehicle slowed down and eventually stopped. The vehicle was taken to an independent mechanic, where it was diagnosed with a failed vacuum pump. The mechanic informed the contact that the vacuum pump needed to be replaced. The vehicle was repaired. The contact stated that the failure was…

   NHTSA complaint #11760902 · source
4. Filed Aug 23, 2026MIBrakes

   The brake suddenly became impossible to depress more than 3/4 of an inch. Almost unable to stop nearly hitting another vehicle. The dashboard then lit up with a "service brake system" warning. Luckily was only a few minutes from home brought it home and began the search for the issue. The brake vacuum pump failed. Unsure of further damage at this point. It being Sunday am unable to contact a shop or dealer.

   NHTSA complaint #11758896 · source
5. Filed Aug 19, 2026CTBrakesEngine

   While driving, I suddenly smelled something burning. Immediately after, a warning popped up stating 'Engine power is reducing,' the check engine light came on, and I experienced a sudden, near-total loss of power braking assist, making the brake pedal extremely hard to press. I had to use intense force to bring the vehicle to a stop. A scan of the vehicle's OBD-II codes revealed codes P0556 (Brake Booster Pressure Sensor Circuit), P0014 (Exhaust Camshaft Position Timing…

   NHTSA complaint #11757862 · source
6. Filed Jul 30, 2026PABrakes

   While driving north in interstate 79, the brakes became very hard to push making it difficult to stop the vehicle. We got off the interstate and proceeded back home. The brakes were as hard as a rock to push and it was difficult to stop the vehicle. When this happened, the check engine light came on and stayed on. It was very dangerous to drive due to the brakes not working properly and the stopping distance was greatly reduced and it was difficult to stop the vehicle…

   NHTSA complaint #11753729 · source
7. Filed Jul 23, 2026NHBrakesEngine

   Vacuum pump failure causing sudden and unexpected hard brake pedal and loss of braking coming off the highway. Ended up catastrophic engine failure. This is the SECOND incident with this vehicle of the exact same problem. GMC refuses to address this issue and continues to risk the lives of their customers.

   NHTSA complaint #11752293 · source
8. Filed Jul 18, 2026ILBrakes

   I was traveling down the interstate at 70mph. Traffic began slowing ahead of me. I hit the brakes and the pedal was rock hard and I could not stop my vehicle safely. Service brake assist light flashed momentarily. Ended up being the vacuum pump. I was told by the dealership I had it towed to that the vacuum pump had broken off and failed. This was an absolutely horrifying situation that could have caused severe injury or death.

   NHTSA complaint #11751242 · source
9. Filed Jun 8, 2026ALBrakesEngine

   During my daily commute to work on the interstate the service break assist message came on my dash and when attempting to break the pedal was very hard, to the point where I had to push extremely hard and quickly realized I had to brake much much soon than normal to prevent hitting other vehicles. Sudden loss of brakes put me and other drivers at risk due to my near inability to slow down or stop and the sudden and unexpected nature of the event.

   NHTSA complaint #11742854 · source
10. Filed Jun 8, 2026VABrakes

    The brake vacuum pump had a catastrophic failure which resulted in the immediate loss of all brakes in the vehicle. I had the vehicle repaired only to find that GM has issued numerous repair bulletins to dealers and mechanics. This appears to be an issue known to them. As the vehicle was repaired, the parts are no longer available for inspection. This was a danger to me and others around me because I was traveling 60mph down hill with no means to slow or stop. I narrowly…

    NHTSA complaint #11742755 · source
11. Filed Jun 8, 2026AZBrakesEngineOther / Unknown

    On June 7, 2026, I was driving my 2020 GMC Terrain. I was going at about 40MPH along a very busy main road. While slowing for a red light the Check Engine Light turned on and the car displayed a notice about reduced engine power. Seconds later, the brake pedal became stuck and would not press down all the way and I lost braking ability. The car rattled/shook violently, made a grinding noise, and then the engine shut off and the car stopped abruptly, narrowly avoiding hitting…

    NHTSA complaint #11742733 · source
12. Filed Jun 6, 2026NHBrakesEngine

    I am a [XXX] resident. While commuting to work in [XXX], my GMC Terrain experienced a sudden, catastrophic failure of the brake vacuum pump while traveling at highway speeds. When I attempted to slow down for the exit, the brake pedal instantly became extremely stiff and nearly impossible to depress. I realized I had suffered an absolute loss of power braking assist. To avoid a high-speed collision with heavy highway traffic, I was forced to deliberately steer onto the…

    NHTSA complaint #11742437 · source

Source: U.S. National Highway Traffic Safety Administration (NHTSA) Office of Defects Investigation public data. Complaints are submitted by owners and are not verified by NHTSA or by us; a complaint does not prove a defect exists. View this vehicle on NHTSA.gov Methodology