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really awful
Crashes / Fires:
1 / 1
Injuries / Deaths:
0 / 0
Average Mileage:
35,344 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 Sierra electrical problems

electrical problem

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2012 GMC Sierra Owner Comments

problem #6

Oct 232015


  • 75,000 miles


The contact owns a 2012 GMC Sierra. The contact stated that the vehicle experienced a loss of power which resulted in a front end collision with a guardrail. When the failure occurred, all the warning indicators illuminated. The vehicle was able to be operated after the crash. The vehicle was not taken to a dealer or independent mechanic to be diagnosed or repaired. A police report was filed. There were no injuries. The manufacturer was not made aware of the failure. The failure mileage was approximately 75,000.

- Atlanta, GA, USA

problem #5

Aug 202015


  • 29,994 miles
While moving with transmission in drive, the ignition switch can be switched off. By doing so, the power steering and brakes fail to function properly. The steering wheel will lock, not allowing to steer. There have been a safety concerns with other GM products, why not this model? this is a safety concern.

- Wichita Falls, TX, USA

problem #4

Jul 022015


  • 25,072 miles
Check engine light illuminated. Took truck to local Chevrolet dealer for repair and they discovered the wires had been chewed through. I read that GM uses peanut oil on wires in order to install them easier. Looks like this attracted a mouse, squirrel, chipmunk, or other creature and it chewed the wires. Luckily it did not affect the operation of the truck but it could have led to a short circuit that could have caused a fire. I feel this needs to be thoroughly investigated. And GM needs to create some kind of animal repellant to spray on the wires after vehicle assembly.

- Mcdonald, PA, USA

problem #3

Jun 122014

Sierra 4WD 8-cyl

  • Automatic transmission
  • 60,000 miles


The contact owns a 2012 GMC Sierra 1500. The contact stated that while driving 55 mph, the right and left turn signal and safety belt chime stopped working. Also, the radio malfunctioned and the vehicle veered to the right. The manufacturer was not contacted and the vehicle was not diagnosed. The vehicle was not repaired. The failure mileage was 60,000 and the current mileage was 65,274. Updated 10/2/14 the consumer stated that the interior lights also went out. The vehicle was repaired under recall. Updated 3/9/15

- Tsaille, AZ, USA

problem #2

Jan 022013


  • 10,000 miles
Apparently GM uses peanut oil to lubricate wiring so they can more easily insulate, etc (accorging to the GM dealer). This attracts rats and mice which chew up the wiring - potentially impacting sensors and other items controlling cruise, stability/traction control, and any number of electrical systems that the driver may be relying upon for safety. I actually had map sensor wires chewed up that disabled my stability/traction systems and inhibited engine performance. Luckily for me it happened in my driveway rather than on the highway. Dealer claims it is not warranty item even though caused by a process that GM elects to use in building the vehicle. This could impact any/every vehicle that GM builds with use of peanut oil (may indeed be all of their models).

- Santa Clarita, CA, USA

problem #1

Oct 172012


  • 12,000 miles
Vehicle was taken to GMC dealer for headlight defect and we were informed that they would have to order parts. Drove truck back to site and while truck was running but stationary smoke was observed coming from the engine compartment. When the hood was raised the entire truck became engulfed and completely burned.

- Beckley, WV, USA

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