Huge win for car owners! All TSBs to be made public. The Center for Auto Safety just made the NHTSA (US Government) make public the full text of all TSBs from now on. They are the same organization that has petitioned the NHTSA & filed lawsuits to protect car owners over exploding gas tanks & other major safety issues. Whenever you drive in your car, you are safer thanks in part to a lot of work over the years by this small but very effective consumer advocacy group.

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really awful
Crashes / Fires:
1 / 0
Injuries / Deaths:
1 / 0
Average Mileage:
33,438 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2012 GMC Terrain engine problems

engine problem

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2012 GMC Terrain Owner Comments

problem #5

Apr 292016


  • miles


Sudden unintended acceleration when vehicle shifted from park to drive, resulted in extreme high speed acceleration and no control of vehicle. This resulted in a high impact crash into garage side wall. Also air bag did not deploy. Assume throttle wide open causing sudden acceleration. Insurance report, and police report pending

- West Bloomfield, MI, USA

problem #4

Mar 312015


  • 45,000 miles
Summary: I had to decide to brake or shoot through a yellow light, going about 35 mph, I braked! all of a sudden I heard a clunk and then alarm ding from the dash as well as message "service stabiltrak" then "reduced engine power". I was unable to go any faster than 25mph. I drove in this mode for about 2 miles taking the back streets to my destination. At destination shut vehicle off to see if this would reset something, it did! it was super scary. So now terrified to brake hard.

- Costa Mesa, CA, USA

problem #3

Sep 182015


  • 73,115 miles
The contact owns a 2012 GMC Terrain. Upon starting and driving the vehicle, the speedometer failed to function. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 73,115. The VIN was not available.

- San Antonio , TX, USA

problem #2

Nov 112013

Terrain 4-cyl

  • 44,039 miles
On 8/2/12 I purchased my GMC Terrain brand new in ashland city, tn. I moved to West palm beach in October 2012. The current miles on the vehicle are 44,039. I got an oil change, filter and multi-point inspection on 10/24/13 by the local GMC dealer. On 10/23/13 I took my vehicle in to have a recall repaired at schumacher Buick/GMC. The recall # is 12312. A month later the vehicle would lunge sharply forward while driving and a heavy shaking vibration (both while driving and at a stop) below my feet in the vehicle (floor board). I took the vehicle to schumacher Buick/GMC 3031 okeechobee blvd, on 11/11/13 and it remained until 11/15/14 and the problem was not identified. I returned the vehicle for the same problem on 12/21/13 (same dealer) and it was picked up on 12/31/13. The first service advisor was rob deal he told me that the vehicle shifts its drivability to the driver and nothing was wrong. I took my vehicle back a second time for the same problem this time (it was getting worst) my rep was "[xxx]". he said it was the "eco" button in the car, if pushed makes the car run rough." On March 7, 2014, I contacted GMC corporate office and spoke to sherry and requested a full analysis of my car. This time I went to another GMC dealer locally (lake park schumacher) and my service tech was [xxx]. per [xxx] it is a transmission issue -left on my voicemail and saved" specifically he said it was the "control pressure valve causing it to lunge forward and it was improper." He said it was "uncommon to see this issue." The reason I took the vehicle in is that I almost rear ended two people while driving due to the vehicles lunges and have my body jolted into the glass the force was so strong with the lunge. I fear for my safety and that of my 12 year old daughter in this car. I was contacted on 3/13/14 that the vehicle was ready for pick-up and it had been fixed. Information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6).

- West Palm Beach, FL, USA

problem #1

Apr 252013

Terrain 6-cyl

  • 5,035 miles
I started out driving on highway road at approximately 5:45pm traffic was moderate, my speed was about 30-35 mph. All of a sudden I heard a clunk and then alarm ding from the dash as well as message "service stabiltrak" then "reduced engine power". I was unable to go any faster than 25mph. I drove in this mode for about 2 miles in traffic, when reaching open highway (no traffic) the vehicle would not shift by itself. I had to accelerate then let off the gas, tap pedal then the vehicle would shift. I was able to do this multiple times until reaching about 45mph. I pulled off into a neighborhood, shut vehicle off to see if this would reset something, it did not. The vehicle was in this state when I arrived at the dealership service department at approximately 6:05pm. Dealership logged following on service request: 5043 found code P228C ran diag could not duplicate problem fuel psi at spec raises to spec test drove on highway did not duplicate condition found no bull on condition test drive numerous time, could not duplicate concern. Miles out 5067.

- Columbus, OH, USA

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