2019 GMC Terrain Brakes Problems

Brake assist light came on and brake pedal became stiff/hard to push. Vehicle struggled to brake. Replaced brake pads and checked brake fluid. Brakes still inoperable. Check engine light came on for vacuum pump. When replacing pump, metal shards and pieces were falling out when original was removed. Once replacement was installed vehicle began hesitating to start and run.

I am driving a 2019 GMC Terrain SLT, and I have a serious concern regarding a recent service experience. On 02/10/2026, I had an oil change and a complete vehicle inspection performed at Kunes GMC Greenfield, Wisconsin. After the service was completed and I returned home, I noticed an unusual noise coming from under the engine hood. I immediately went back to the dealership and informed them of the issue. I was asked to return the following day (02/11) for further inspection. After their investigation, I was informed that the vacuum booster had failed. It appears that this issue was not identified during the original inspection, and I was the one who brought the noise to their attention. From my understanding, vacuum pump/booster issues are common with many 2019 GMC Terrain models. I am surprised that this has not resulted in a recall, especially considering the potential safety risks it poses to me and my family. What concerns me even more is that this issue was not detected during the dealership’s inspection. If it had worsened, it could have led to a serious safety situation. I had to spend $450 today to repair what appears to be a manufacturing-related defect. I respectfully request that this matter be escalated and that my claim for reimbursement be reviewed. I would appreciate your assistance in helping me pursue compensation for this expense.

Failure of the cam driven vacuum pump causing brake failure. Leading to a hard brake pedal which increases risk of a crash. Debris from the broken vacuum pump can fall down into the engine causing a catastrophic failure of the engine needing a replacement. This happens with little to no warning. Warranty companies will not pay to repair the known issue. A recall needs to be issued for this to provide a fix. This is a family suv and I do not feel safe putting my children in a vehicle that can endanger their lives and safety.

When approaching a stop sign, the brake pedal became extremely hard I was unable to stop, and rolled through the intersection avoiding collision. I was able to slow down enough to engage the emergency brake. There are no lights on the dash.

Driving approximately 70mph on interstate. Came to a slight hill, gently applied brake pressure, brakes become hard to apply/would not apply. After diagnostics, found Brake Vacuum Pump with damaged fins.

I was backing out of the driveway, and it was extremely hard to brake enough to stop the car. I immediately parked back into the driveway. I had to stand on the brake to completely stop. Vacuum pump was completely busted and in many pieces.

While driving the vehicle the car went into limp mode and the back brakes stopped working. The car had to be drifted into a parking lot. The vacuum pump malfunctioned and has damaged the engine. If it was me in the driver seat instead of my partner, the incident would’ve 100% been an accident. The car was really unable to be controlled and we just happened to have that space that was empty to turn into. The car gave code when this happened. When getting a tow the car also wouldn’t take itself out of park or start to go into neutral to move the car to get it towed. Nothing is working with each other anymore and we were on a busy road of people when our brakes just went out.

The contact's wife owns a 2019 GMC Terrain. The contact stated while driving 70 MPH and depressing the brake pedal, the brake pedal was firm, and the vehicle failed to respond as needed. The check engine warning light was illuminated. The contact stated that upon depressing the brake pedal with excessive force, the vehicle responded as needed. The contact stated upon inspecting underneath the brake booster, the contact noticed a lot of debris due to lack of vacuum pressure. The dealer and the manufacturer were notified of the failure and referred the contact to the NHTSA Hotline to report the failure. The vehicle was not diagnosed or repaired. The failure mileage was approximately 80,000.

Vacuum pump broke and car has no brakes

While driving the breaks completely locked up and the smell of exhaust entered through vents. Ran a code machine indicating that the break booster power vacuum pump was needing replaced. There are no other issues with my vehicle that would cause it to malfunction out of no where.

Breaks went out on vehicle with no warning or lights on dash. Nothing prior or now indicating any issues with breaking system.

Vacuum pump failed causing hard brake pedal and the inability to properly stop the vehicle. Thankfully I made it to a safe area and had the vehicle towed. No warning light or engine service lights ever illuminated. Once it was taken apart the bearings were disintegrated and metal shavings are in engine components.

At 86,000 miles information board on dashboard alerted “Service, Brake Assist” upon braking from coming off of interstate. Diagnosed to a failed cam shaft driven Vacuum pump for power brake booster, next to no braking power with little to no warning what so ever. Terrible design from GM. Near miss collision due to brake failure with no warning. This needs an immediate attention through the engineering department to create a redundancy within the system. Nearly caused a very bad accident with my [XXX] and [XXX] daughters in the vehicle while fiancé was coming to pick me up from being on the road as a OTR truck driver. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The brake vacuum pump failed. I am extremely fortunate this happened at a rest stop after being on interstate 80 for numerous miles. Had this happened at highway speeds it would have been catastrophic for myself and most likely others. I do not have the part. The problem was confirmed and the psrt was replaced by Mavis Discount Tire in Mountain Top, PA There were no warning lights, signs, or symptoms prior to the malfunction. It is my understanding that GM has recalled the part on other models, but did not include the Terrain in the recall. I believe it should be before someone is seriously injured.

I was riding on the freeway when my brakes failed. i was not able to press down on my brakes with zero warning. I had to swerve to miss cars and pull on the shoulder of the freeway and my car still would not slow down. I finally got from 65 to 35 and pressed on my emergency brakes. I stopped the vehicle then my engine light came on and I got my car towed to the car shop where my car would not stop and suffered internal damage to my engine from the brakes and vacuum pump

The contact called on behalf of her husband who owns a 2019 GMC Terrain. The contact stated that while her husband was driving approximately 50 MPH, the brakes seized, and the contact veered off into a lot to park the vehicle. The vehicle was towed to an independent mechanic where the vehicle was diagnosed. The contact was informed that the brake vacuum pump and the timing chain needed to be replaced. The vehicle was repaired. The manufacturer was notified of the failure. The approximate failure mileage was 72,000.

The brakes failed with zero warning while driving. Car only has 60,000 miles. Extremely dangerous and it looks like it has been reported and known issue! It needs to be recalled.

on two occasions the vacuum pump booster failed causing the vehicle to lose braking ability while traveling on a highway at highway speeds. The vehicles brake completely failed and were unable to be engaged. the part was initially replaced by the dealer at the owner's expense and then the same issue occurred only a few months later. the second occurrence cause additional damage to the camshaft and timing chain causing the vehicle to not even be able to start. The vehicle was inspected by the servicing dealer and found metal shavings in the oil as well as extensive damage to the engine.

My family and I were returning home from vacation in another state, and while we were driving on the interstate, an alarm popped up on the DTC stating ruduced engine power. I tried to start slowing down so I could take the next off ramp and could not push the brake pedal in. I had absolutely no brakes trying to slow down from interstate speed. I was able to pull into a gas station parking lot while avoiding other vehicles. I was very lucky not to get in an accident. I had to have it towed to the nearest service center and was charged nearly $4000 for repair. The car has not ran right since we recieved it back. I called them back to let them know and was told the only way I would not have to pay to have it looked at was to bring it back to them. That shop was four and a half hours away from my house. The car was less than twenty miles out of the warranty when it broke down (nine miles to be exact), then they lied on the the paperwork and put the milage after they test drove it.

The contact owned a 2019 GMC Terrain. The contact stated that while the wife was driving at approximately 60 MPH, the brake pedal was depressed and it felt stiff. The vehicle failed to decrease in speed and as a result, the driver merged to the shoulder of the road however another vehicle crashed into the front driver side of the vehicle. The driver was able to merge to the shoulder of the road where the road bumps were able to decrease the speed of the vehicle. The ABS warning light was illuminated. The driver, front passenger, and rear driver's side passenger all sustained headaches and received medical attention via an ambulance on the scene. No occupants in the second vehicle were reported injured. A police report was taken at the scene and the vehicle was towed away. The cause of the failure was not determined. The manufacturer and local dealer were not contacted. The failure mileage was 40,000.