2020 Gmc Terrain Complaints

  • Service Brakes, engine, fuel/propulsion System 09/01/2022

    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...

  • Engine 01/26/2026

    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.

  • Air Bags 06/02/2023

    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.

  • Steering, service Brakes, engine 03/04/2026

    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.

  • Service Brakes 02/21/2026

    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.

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