2020 GMC Terrain

1- at 71,000 miles in 2022 brake vacuum pump “exploded” broke into many small pieces in the middle of driving. Causing brakes to lock. Brake pedal was brick hard. Hard to maneuver the car out of traffic without causing a collision. Luckily car was not being driven at high speed. At time of repair costing $1,000 Mechanic informed me that the pump was made out of a non metal material and he could not fish the small particles out of the motor with a magnet. The motor would need to be taken apart, cleaned out and reassembled….. From this point forward the car drives in “low engine power mode” even with repairs completed and codes cleared. 2- 2 years later the same part “brake vacuum pump” exploded again. Another $1000 repair. At this time we discovered that the fine particles that were not removed from motor has now knocked the timing off by 8%. Also it has caused a knick in a seal causing an oil leak under 100k miles $1800 repair. After these extensive repairs…… The car emits gas fumes into cabin. The smell is so strong it can’t be parked in the garage because it circulates through the house. Even when car is not running. The Car can’t be driven because risk of fire or explosion from gas. Fuel system gets cleaned. Injectors replaced. The car temporarily runs without the gas smell. 2 weeks later the gas smell returns Come to find out the fuel pump failed. Search online and find there is a recall for fuel pumps in this same make model and year. But not this vin number. The car has been a headache from day 1. Recall the whole car at this point, to have so many faulty parts in such major systems of a car is crazy.

Catastrophic engine failure; no warning lights,etc. took place on or about end of January 2026. Car completely died and would not start. Car towed to dealer (GMC Blaise Alexander, Hazleton, PA) Vehicle inspected by dealer master mechanic and others. Engine completely disassembled. Unable to repair. No warnings, lamps, messages or other symptoms prior to failure. Tremendous expense had to be incurred by us over this incident. We had to purchase a new car. Terrain had been meticulously maintained by dealer since purchase. We still had over one year of payments remaining. Expected car to last closer to 200,000 miles. A new engine could have been installed, but cost was too expensive. We lost all of our equity in the vehicle.

The airbag system on my 2020 GMC Terrain has an intermittent malfunction. The airbag warning light turns on and off and the diagnostic code B0014 has been identified by a dealership. When the warning light is on, the airbag system may not deploy properly in a crash, creating a safety risk. The vehicle has approximately 49,000 miles. The problem has occurred for about three years. The dealership repaired the issue when the vehicle was first purchased and the light went off temporarily, but it returned a few months later. A second dealership attempted a repair and again the light went off temporarily before returning. The issue continues to occur intermittently. The warning lamp for the airbag system appears on the dashboard. The vehicle has been inspected by dealerships but the problem has not been permanently fixed.

I was driving 55 miles an hour on an Expressway. And suddenly my truck just shut off.The brake became very hard unable to break very scary situation for me and my children. Engine power was reduced and would not start, many errors came up. The vacuum pump failed, which also caused the cam shafts to fail.The vacuum pump exploded into pieces and sent metal into my engine.

While driving I received a "service brake assist system" alert and a check engine light. After this happened the brakes were extremely hard to press. I had to put my entire weight on the breaks to stop the car. The brake "assist" feature really is making the brakes functional. We were able to safely get to the side of the road. We found a vacuum pump failed and needed to be replaced. There was no sign that this was failing; it worked, then it didn't.

The contact owns a 2020 GMC Terrain. The contact stated that while driving in cold weather at various speeds; moisture accumulated and deactivated the charger, causing the vehicle to go into LIMP Mode and lose drive power. The vehicle was taken to the dealer, who diagnosed the vehicle and determined that the charger air cooler was defective and needed to be replaced. The dealer also wanted to place an air deflector on the vehicle. The contact was informed of a service update for the failure however, the VIN was not included. The vehicle was not repaired. The contact researched and learned that in Canada, the issue was being remedied with a bra apparatus and a thermal wrap for the engine to prevent the failure. The manufacturer was made aware of the issue and confirmed that the VIN was not covered. The contact was waiting to hear from a supervisor. The failure mileage was approximately 140,000. The VIN was unavailable.

I own a 2020 GMC Terrain with approximately 110,000 miles. While driving in winter, the vehicle suddenly lost cabin heat and defrosting capability. The temperature gauge began fluctuating and the cooling fans continued running after the vehicle was shut off. A mechanic diagnosed the cause as a cracked radiator that allowed coolant to leak out, which is a known frequent failure on this model. Because the heater stopped working in sub-freezing temperatures, this created a safety hazard due to lack of defrosting and heat while driving. The failure occurred without warning, and no coolant warning light was displayed before the heater stopped working. The vehicle was not overheating at the time, but the loss of heat and defrost made winter driving unsafe.

I noticed a sticker in driver door stating recall however no evidence. The vehicle will not pull hills, back up on a hill and will not accelerate over 25 miles per minute. Dangerous to drive on roads. Took vehicle to a GMC dealer for diagnostic test, received the report for what the report found. Took the report to auto shop to get repaired however the vehicle still continues with same issue. Took the vehicle to another auto shop. I was informed of some differences added issues. I had those issues fixed. The vehicle still running the exact way after all of the repairs. The top hood on the vehicle paint starts peeling after a year of owning it. I purchased the vehicle at Kia of Gardendale 2020. No one had any answer regarding the situation. Very disappointed with a GMC vehicle. I just want to know the mystery.

While driving down the interstate a notice popped up on my dash about the brake assist. When I attempted to slow down the vehicle to safely pull over the brake pedal was very hard to push. I was able to slow the vehicle to a complete stop but needing to use both feed and press hard with all my weight. Once the vehicle was parked and shut off I turned it back on to have the check engine light pop up on the dash. I contacted Onstar and was towed to a dealership. The brake vacuum pump had broken off at the cam shaft and required extensive repairs. It is my understanding that this is a common occurance and there were previous recalls on the other style Terrains due to the same issue. yet they used the same part on the newer body style being fully aware of the design flaw.

The contact owns a 2020 GMC Terrain. While the contact’s wife was driving approximately 40 MPH and attempting to depress the brake pedal to pull into the parking lot of Walmart, the braking distance was extended while bringing the vehicle to a complete stop. The driver used excessive force on the brake pedal using both feet. The vehicle was towed to a certified mechanic, who diagnosed the vehicle and determined that the brake vacuum pump had failed. The vacuum pump had fractured where it was connected to the camshaft, causing pieces to enter the engine. The brake vacuum pump and the connector were replaced. The manufacturer was made aware of the failure. The failure mileage was approximately 156,000.