Problems · by component

2012 GMC Terrain power train problems

37 owner complaints to NHTSA about the 2012 GMC Terrain cite power train, 10% of all 370 complaints for this model year.

Complaints
37
10% of all complaints
Crashes
0
Reported by owners
Fires
2
Reported by owners
Injuries
0
Reported by owners
01 —Owner reports

What owners say about the power train

Verbatim from NHTSA complaints, newest first
“1. The engine suddenly lost power while driving during evening rush hour and the vehicle would no longer accelerate. 2. Because the vehicle could not maintain speed, I was unable to keep up with traffic, creating a serious safety hazard that could have resulted in a major accident. 3. The vehicle has been inspected by an independent service center for diagnosis. 4. During the incident, the “Engine Power Reduced” warning indicator illuminated just before the loss of power occurred. 5. As the vehicle slowed and came to a complete stop at an intersection, it remained unresponsive. When the traffic light turned green, the vehicle would not accelerate at all.”
Owner complaint to NHTSAFiled Nov 16, 2025Power train, Electrical system, EngineODI 11699710
“GMC Consumer Relations Subject: Structural Undercarriage Safety Defect – 2012 GMC Terrain SLE Vehicle Information: Year/Make/Model: 2012 GMC Terrain SLE VIN: [XXX] Mileage at Purchase: 148,305 Date of Purchase: [XXX] Location: Rochester, New York I am filing a complaint regarding a severe undercarriage safety defect in my 2012 GMC Terrain SLE. The rear undercarriage of this vehicle shows heavy structural corrosion on suspension brackets and mounts. The condition produces clanging noises during normal driving, and an independent licensed mechanic has refused to work on the vehicle because the suspension integrity is unsafe. When I returned the vehicle to the dealer, I observed additional brackets being attached under the rear subframe area, suggesting reinforcement of compromised structural points. This confirms that the corrosion directly affects suspension geometry, alignment, and stability. This corrosion is not cosmetic. It is advanced structural deterioration affecting the mounting points for trailing arms and lateral links. These components are critical to safe turning, stability, and control. The corrosion compromises the ability of the suspension to keep…”
Owner complaint to NHTSAFiled Sep 15, 2025Suspension, Power train, WheelsODI 11687398
“hello i'm writing this letter to inform you about my 2012 Terrian i have had nothing but problems with the motor and now the muffler system i have had all recalls done on this and GM is well aware of this problem i have a dealer ship to replace the timing in this motor and still uses oil and still have all the problems after the recalls have been fixed now they want me to pay over $3,000 to have new catalytic converters fixed on it now after paying $2800 for a new timing seems to me GM likes to fix the cheap stuff on these cars and make customers pay for the expensive parts must people can't afford this and junk the vehicle i will not i'm going to fight for what is right the dealer ship even told me when i took it back in to see what the code was for that GM is well aware of it and not worth putting the money into the car this is not right for customers to spend this kind of money GM needs to handle this.”
Owner complaint to NHTSAFiled Apr 10, 2024Power train, Engine, Fuel/propulsion systemODI 11582154
“The contact owns a 2012 GMC Terrain. The contact stated that while driving at 65 MPH, the vehicle inadvertently lost all motive power. The contact was able to pull to the shoulder of the roadway, where the vehicle was able to restart, but failure persisted. The traction control warning light was illuminated. The vehicle was towed to an independent mechanic, who was able to diagnose the failure, but the contact was unable to recall the specifics. The vehicle was repaired. The manufacturer was not notified of the failure. The failure mileage was unknown.”
Owner complaint to NHTSAFiled Mar 20, 2024Power trainODI 11578481
“My 4 cyl. AWD GMC Terrain has had excessive oil use which caused premature failure of the timing chain, loss of power/compression, blown engine, damage to exhaust manifold, cellinoids, and melted the catalytic converter. Its was a road safety, poor emissions due to failed catalytic converter. Headlights are too bright for oncoming traffic at night. Another road & safety hazard. Auto warranty is refusing to cover parts listed above caused by the timing chain and excessive oil consumption problems.”
Owner complaint to NHTSAFiled Jan 24, 2024Power train, Exterior lighting, Unknown or otherFire reportedODI 11567406
“The contact owns a 2012 GMC Terrain. The contact stated that while driving at an undisclosed speed, the vehicle inadvertently lost motive power. The contact was able to coast the vehicle to the shoulder of the roadway, and the vehicle failed to restart. No warning lights were illuminated. The vehicle was not taken to the dealer nor an independent mechanic. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was unknown.”
Owner complaint to NHTSAFiled Jan 16, 2024Power trainODI 11565815

Showing 6 of 37 reports. Read every report on NHTSA.gov.

Data from NHTSA Complaints API (owner reports, unverified) · synced Oct 28, 2026NHTSA vehicle page

Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.