Vehicle Shows on the Dash readout that the truck must keep going to clean out exhaust keep Driving, then comes to a Slowdown, and on a slight hill Stops. When you shut it off, and start it up again, it goes about a Mile, states the same thing on the dash panel, then starts to slow down, I was in the Desert of New Mexico, Had left Flagstaff, AZ. an hour before this started happening. I had no Previous warning. Took 6 hours to reach a GMC Service Center. usually takes 2 hours to reach the same town. Cortez, Colorado. They Could NOT Help Me, they had to referred me to a Service Center in town, that Put me on his machine, and Made the Vehicle Heat up, Run HOT, and Exhaust itself for two hours, this got me to my home in Monte Vista, CO. Then No further Problems until about a Month later i started getting the Same Messages, i took it to a Service Center in AR. where he Forced the Vehicle to Get Hot, exhaust itself for four and a half hours, to Clean it out, and Clear my dash Pannel.

- Monte Vista, CO, USA

Diesel Fuel Gage is Not reading Properly. On a Full Tank which use to say I have approx., until 468 Miles, until I Have to re-fuel. Now Reads Less then 288 Miles, on a Full tank. I have reported this Problem to the Town and Country, GMC, Dealer, of Alamosa, CO. when I have taken My Vehicle in for Service on several Occasions, and Nothing has been done about it. and GMC, has still NOT replaced the Recalled Passenger Air Bag. My Wife sits there and Could be Killed Should Her Airbag be deployed. Thank You [XXX] INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).

- Monte Vista, CO, USA

I have a 2013 GMC Sierra, purchased new in 2012, has approximately 35,000 miles. The check engine light came on while driving and suddenly another light came on. Then a third light came on claiming poor engine fluid quality. I immediately stopped at an auto parts store and put DEF fluid in the pickup and continued to drive thinking the lights would go out, but instead a warning was flashing on the dash that says after so many miles the truck will be slowed down. We started getting nervous because we were driving on the highway and if the truck suddenly slows down whilst driving in highspeed traffic, our slower vehicle would potentially cause a collision and put us and others in harms way. In reading your own safety site, there is a recall on the vehicle regarding faulty airbags, so it could be even worse! In our investigations of our current issue, we have found that there was a lawsuit from 2019 against GM and their faulty fuel system with their trucks. See link here https://www.detroitnews.com/story/business/autos/general-motors/2019/08/07/lawsuit-says-gm-sold-trucks-not-compatible-american-diesel-fuel/1943084001/ many people on many different forums have also complained about this same problem with no fixes, the only suggestions are to remove the emissions parts and refab the motor. GM tells them that they need to only use their specific DEF fluid, which is steering. GM is very well aware of the problems, because they have employees following these forums and commenting on them.(Dieselplace.com) The truck can be made available for you to see/inspect and I refuse to drive the truck until this issue is resolved.

- Dryden, VA, USA

I'm getting an inaccurate fuel gauge reading.

- Tonawanda, NY, USA

P21dd code low voltage. This is second time it has been replaced. 62145 miles on truck..

- Piqua, OH, USA