2019 GMC Terrain

While driving my 2019 GMC Terrain with three children as passengers, the vehicle developed a braking/engine problem. The brake pedal became very hard, and the vehicle subsequently became undrivable and would not start. I received no advance warning through the GMC app indicating that the vacuum pump was failing. The vehicle was towed to a GMC dealership. The dealership diagnosed a failed vacuum pump and advised that the engine requires replacement, with an estimate of approximately $11,238. I purchased this vehicle new. I am very concerned that a vacuum-pump failure can result in reduced brake assist/increased brake-pedal effort and major engine damage without adequate advance warning. Three children were in the vehicle when this occurred, and the sudden change in braking created a serious safety concern for everyone in the vehicle. The vehicle is currently at the GMC dealership. I have requested that relevant parts be preserved and am requesting GM Policy Assistance with the repair.

On Saturday, August 15th we were driving on the freeway when with no warning the check engine light came on and the vehicle began to run poorly, and then the vehicle lost electrical power and it became difficult to steer and the brake pedal became stiff, making it difficult to stop and pull over. The vehicle would not start on command but kept running very poorly, it also became impossible to shut the vehicle off until it seized. It was later towed to a local repair shop, and today, Friday August 21st the shop confirmed that the vacuum pump on the brake assist failed and it would need a total engine replacement.

The car’s brakes hardened on the highway, posing a life-threatening danger, right before the engine died. Following a tow to the dealership’s service center, an initial inspection revealed a broken vacuum pump and broken camshaft. The dealership stated that there was evidence that camshaft debris may be scattered throughout the engine. No further inspection has been done at this time due to the probability of major engine damage and/or potential repairs.

While driving my 2019 GMC Terrain on local roads, the vehicle suffered a sudden and complete failure of the braking system. The brake pedal became extremely hard to press, and the dashboard displayed a critical error message stating 'Engine Power is Reduced.' during this frightening safety incident i felt lucky to bring the car to a stop without an accident. The vehicle had to be flatbed towed to a repair facility. This sudden loss of power braking is a known, documented defect matching the engine-driven brake vacuum pump failures currently subject to federal class-action litigation (Thieme v. General Motors). I am requesting a formal safety investigation into why the GMC Terrain was excluded from previous GM vacuum pump recalls despite posing an identical, life-threatening risk to occupants."

While driving the vehicle became extremely difficult to stop I was advised that the Vacuum booster pump was broken and it needed to be replaced. This was first completed 09/24/25 by Gateway tire and service center. I was advised that there was a service bulletin for the issue. Then I have had the same thing happen and I returned the vehicle to the same repair shop and I was advised that the Vacuum booster pump was broken and it caused the exhaust camshaft to break, as well as the timing was out. The shop had to replace several things in order to repair and I was responsible for the cost. There was no warning before either of the incidents.

The turbo went completely out at around 105k miles while I was driving to work. I had to coast into a repair shop because it was smoking and wouldn’t go over 20mph and then have it towed to the place that repaired it. Since then, the transmission is having trouble shifting gears. The car struggles to accelerate and I have to go abnormally slow after coming to a complete stop in order for the car to get into gear. The onstar diagnostic says everything is fine but it is clearly not fine.

The contact owns a 2019 GMC Terrain. The contact stated that while stopped and attempting to turn to exit a highway ramp, he observed a loud banging noise emanating from the engine compartment. An "engine reduced power" message appeared. The vehicle then went into limp mode, and when the brake pedal was depressed, it was stiff as a rock. The vehicle coasted while he continued attempting to depress the brake pedal, and it eventually slowed down. The vehicle was steered to the side of the road and turned off. When the vehicle was turned back on and he attempted to depress the accelerator pedal, the vehicle did not accelerate. The vehicle was taken to his mother's residence approximately 100 miles away in limp mode and parked. The vehicle was not diagnosed or repaired. The contact stated that his brother, during an inspection of the vehicle, removed the vacuum pump and noticed that it was broken with numerous pieces that had gone into the engine. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 76,000.

ENGINE BREAKDOWN 1.5TURBO IN 11/28/25 WITH 16820 MILES ON IT. IT IS NOT AVAILABLE I HEARD A BANG AND SMOKE OUT OF BACK LOST POWER WHILE DRIVING ON THE HIGH WAY DAMAGE WAS CONFIRMED BUY A DEALER GOODWIN CHEVROLET IN BRUNSWICK ME YES BUY GM DEALER. NO THERE WERE NO WARNING LAMPS OR OTHER SYMPTOMS BEFORE FAILURE. CAR WAS CHECK ON 3/30/2023 AT 10383 MILES FOR SHAKING AND LOSING POWER.CAR DID COME OUT IT TOOK IT TO LEE GM DEALER IN AUBURN ME COULD NOT DUPLICATE PROBLEM.

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.