2018 GMC Terrain: brake failure

Filed Sep 30, 2026 · Brakes, Engine · NY

Without any type of warning, I was driving down the road when my car started making a knocking/ticking type noise then my engine light came on. I attempted to hit my brakes and stop, and I had no control. There was no brakes without pushing it all the way to the floor it was very hard to get my car to stop. I managed to get off the road and into a parking lot and now told that I have $5000 worth of repairs, including the vacuum pump, camshaft timing and guides. After reading information I see there is complaints filed regarding this failed vacuum pump and I would just like to report this.

Filed Aug 10, 2026 · Brakes, Engine · MI

While driving my 2018 GMC Terrain, the vehicle suddenly displayed an “Engine Power Reduced” warning and the brakes became extremely hard to press. The vehicle experienced a sudden loss of normal power-brake assist while it was in motion, creating a serious safety risk because significantly greater pedal force was required to stop the vehicle. I was able to pull over safely. After stopping, the vehicle would crank but would not start. The vehicle was towed to a GMC dealership for inspection. The dealership documented that the vehicle had a suspected failed/broken vacuum pump, a damaged exhaust camshaft, and a damaged exhaust camshaft actuator. The dealership subsequently documented that the engine was severely sludged and stated that the sludge caused the vacuum pump to fail, which then caused the exhaust camshaft to twist and damage the exhaust camshaft actuator. The dealership’s written diagnosis recommends replacement of the exhaust camshaft, exhaust camshaft actuator, vacuum pump, and associated one-time-use parts. The dealership has also documented diagnostic trouble codes P0014 and P0017. The failed vacuum pump and related components should be available for inspection upon request. The vehicle has been inspected by a GMC dealership, which has documented the suspected vacuum pump failure and resulting engine damage. The sudden loss of power-brake assist occurred while the vehicle was being driven and created a potentially dangerous loss of braking capability. I am reporting this because I believe the failure of the vacuum pump and resulting loss of brake assist may represent a safety-related defect requiring investigation, particularly because the vehicle experienced a hard brake pedal without prior warning.

Filed Jul 14, 2025 · Brakes, Electrical · WV

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 federal safety agency 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.

Filed May 13, 2024 · Brakes, Electrical · KS

Safety was put at risk when brakes went out without warning, and unable to use emergency brake at that time. Car was serviced for over $1700, with the mechanics stating that the piece “blew up.”

Filed Apr 4, 2024 · Brakes, Engine · FL

While driving on the interstate the brakes all the sudden stopped working. I was able to stop the vehicle by pulling over to the shoulder of the road. I received a warning saying service brake assist and a check engine light after the brakes went out. The vehicle later shut off and is no start with no warning codes. I am currently towing the vehicle to a mechanic. Several people claim to have the same issue online stating that it is an issue with the brake vacuum booster shearing off in the exhaust cam which then causes major damage to the engine. It appears the same issue exists with several other GMC models that were already recalled

Filed Apr 4, 2024 · Brakes · FL

We were driving back from vacation and while on I-95 the brakes went out. The check engine light came on and the service brake assist light came on. My husband was able to pull off to the side of the road but if it weren’t for already starting to slow down due to an accident we were approaching this could have been much worse. When the brakes went out my husband could hardly press the brake peddle. After researching this appears to be a known issue amongst GM vehicles. It appears to be the vacuum pump that went out. There is an open recall for certain models of GM but not all. This was such a dangerous situation. We literally could have died. This should be a recall for all models as Terrains appear to be largely affected as well from this issue.

Filed Jul 28, 2023 · Brakes, Engine · OH

Last year this time brakes went out at 50 mph power brake module imploded from inside out. The part was on national back order. Second incident car stopped immediately while traveling 40 mph no warnings or anything both incidents could of been horrible . Not sure on second incident the issue yet car is in shop. Both incidents are safety concerns for myself and others. Driving at average speeds and something malfunctioning is a great concern of mine. I contacted GMC no one to talk too just chat and the person on the other side told me it was no concern of theirs all was dumbfounded by the conversation but until I said I was putting on social media and bringing to everyone attention her entire tune changed in regards to part and service. So I researched locally and luckily I found the part they had one left and I was told by dealer that it is an issue on these vehicles. Both safety incidents have been within a year of each other 2022 and 2023

Filed Aug 1, 2022 · Brakes · IL

While getting off the interstate, the brakes failed with no prior warning, or issues. The brake pedal became extremely difficult to depress and stopping distance was greatly increased. Could not come to a complete stop without using the emergency brake. We drove home (about 2 miles from the interstate exit) and about a half mile after the brake failure, a "service brake assist" light illuminated. Vehicle was towed to dealership the next morning. The problem was the vacuum pump exploded and caused vacuum to the brake booster to be lost, making the pedal difficult to push. Luckily this happened at 11pm and there was nobody in front of us, there definitely would have been a collision.

Filed Jun 3, 2022 · Brakes · OH

6/3/22 I went to the grocery store which is on a four lane road. When I left the store I had no brakes. On a four lane stop and go road. The was no warning just nothing peddle to the floor and now check engine light is on. I am reading this same problem repeatedly. I love this car but this is a serious hazard and needs to be addressed. We are all driving around practically rear ending people. I was an inch from the guy in front of me thank God the light changed as I was coming up on him or I would have hit him.

Filed Oct 17, 2021 · Brakes · FL

The vehicle experienced a sudden loss of braking and displayed a “brake assist “ fault message. The check engine light has illuminated. The sudden loss of braking was in a residential neighborhood traveling at 35 mph. I was turning during the loss of braking and was able to narrowly avoid collision with the cars at the intersection because I could not slow to a safe speed. The fault codes have not been read by the dealership yet nor has the repair been completed.

Filed Feb 25, 2021 · Brakes, Electrical · 34,000 miles · OH

When restarting after vehicle "auto stop" I am getting "service brake assist" and occasionally "service ESC" warnings. These warnings were associated with brake failure in gm SUV's and pickups and were subject to a recall. No such recall exists for the terrain. I haven't yet experienced a brake failure but gm seems to want to wait until I do to fix the problem.

Filed Jan 31, 2021 · Brakes · 44,950 miles · FL · crash

My 2018 gmc terrain brakes did not work when coming to a stop at stop lights which caused me to rear end the car in front of me. There was no warning on my SUV nor did I receive a recall on this matter. This happened twice to me in this same vehicle where the brakes did not respond at a low speed causing an accident. This accident just happened to cause damage to my vehicle and the car in front of me.