definitely annoying
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
45,519 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 3500 engine problems

engine problem

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2012 GMC Sierra 3500 Owner Comments

problem #3

May 162013

Sierra 3500

  • 16,400 miles


While pulling my fifth wheel trailer 12500# at highway speed 65 mph pulling a grade the check engine light came on and the reduced engine power message appeared on the dash. This reduced and limited the speed to 50 mph and steps the truck down from there until you can only do 20 mph on the interstate. This issue has happened three times in three months.

- Wyoming , NY, USA

problem #2

Mar 042013

Sierra 3500 8-cyl Diesel

  • 29,958 miles
This started just a few weeks after I purchased the truck, still under warranty. It has been in the shop twice for this. It has happened 3 times. While driving the truck will shut off like you turned the key off. Very dangerous when driving in traffic. Has been in shop twice for this problem, GMC has failed to find or fix the problem. I told them that I would not put my family back into a truck that has the possibility of causing a wreck and getting them hurt. Filed a claim [xxx] with GMC customer service, trying to get some help. Nothing happened. The GMC service center told me that they could not find or fix the problem, and that I needed to pick up my truck. I told them that if they could not find or fix the problem, I would not put my family back into an unsafe truck that could possibly get them hurt or killed. I tried to have someone from GMC upper management contact me so we could come up with a solution. But no one from management would contact me. So I ended up having to trade this truck in for a new one, which cost me money out of my pocket, higher payments, longer terms etc. Don't think it was right that GMC would not stand behind there product. Why is it that GMC did not have to do anything about a safety item that they could not fix ? I was not asking for money or anything like that, just swap it out even for a safe truck that I could put my family in without fear of them getting hurt. But instead, GMC decided to forget about the problem, and it ended up costing me and my family money that could have been used for other things like food, bills, medical etc. Information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6).

- Victoria, TX, USA

problem #1

Feb 262013

Sierra 3500 8-cyl Diesel

  • 90,200 miles
Traveling at 60mph on turnpike pulling long heavy trailer in rain at night with moderate to heavy traffic. Sudden shutdown of all systems. Engine shut off and all electrical systems shut down. Unable to restart or get electrical systems to work. Worked vehicle to shoulder and had it towed to a dealership. Waiting for them to open to diagnose and repair. This mechanical and electrical failure had the potential for a catastrophic incident.

- Union, MI, USA

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