9.3

really awful
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
1,445 miles

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problem #9

Apr 032021

Sierra 2500

  • miles
Tailgate fell down when I had a trailer hooked up. I was parked, then backed up the trailer. Tailgate came down on the jack and scratched the tailgate. There is a recall on some trucks but mine says no recall. Sounds like same issue.

- Fort Wayne, IN, USA

problem #8

Oct 272023

Sierra 2500

  • miles
The rear window of my 2020 GMC Sierra developed major water leaks across the entire window in 2021. GM has documented this issue with a service bulletin and the dealership has documented their resolution to the first repair under warranty. GM knows of this manufacturing issue and continued to install a faulty back window. Not only did the back window leak large amounts of water into the cab causing a potential dangerous mold issue, the security and integrity of the back window breaking or falling onto rear passengers is a major safety hazard. The integrity of the back window falling out into traffic is another safety hazard to consider. GM issued a service bulletin for leaking back windows for their Sierra trucks due to the known problems. GM has documented their problem and remedied a quick inexpensive solution. Many other GM Sierra truck owners have documented their issues and frustration with GM, and the BBB. GM has invested this issue and found the rear window plastic frame was installed or will develop stress cracked in the frame. GM-??s remedy is to use a silicon window caulk and apply the silicon between the outside top section of the glass to the cab. This did not address the safety aspect of the situation. It only delayed the issue temporarily until vehicle owners were out of warranty. GM-??s solution usually only last for one or two years before the issue develops again. After GM and the dearship siliconed the rear window per the service bulletin in 2021, my vehicle once again developed the same leak as before. The dealer ship once again inspected the rear window, but this time told me the issue and replaced the entire rear window because of the -??stress cracks-??. It-??s amazing that GM wants to replace the rear window at the customer-??s expense since I am out of warranty. It preposterous that GM knew of this safety issue and created a temporary correction that would last a short time until vehicle owners are out of warranty and stick them with a bill.

- Whittier, CA, USA

problem #7

May 012023

Sierra 2500

  • miles
Rear sliding window leak and has saturated seat and carpet causing an unhealthy environment. Spoke with dealer and was told it is a design flaw and repairs are not covered under extended warranty. I was also told it is only a temporary fix and -?? leak will reoccur-??. I only realized of the problem when soap residue was seen on the inside of the widow. Dealer gave estimate of repair.

- Hillsborough , NJ, USA

problem #6

Apr 282023

Sierra 2500

  • miles
When towing a trailer a notice to service trailer brakes comes on and the trailer brakes are disabled

- Green Bay , WI, USA

problem #5

Dec 232022

Sierra 2500

  • miles
1. The Engine Block heater sparked and created a small flash underneath the truck. It can be inspected whenever you would like. 2. Electric spark/fire 3. The problem has not been reproduced nor inspected by the dealer. I would not dare to plug it back in. 4. There were not any warning messages. It happened the first time the engine block heater was plugged in. February of 2022.

- Springdale, AR, USA

problem #4

Feb 022022

Sierra 2500

  • miles
DEF Emission system failure. Total component breakdown requiring replacement. Parts unavailable.

- Tafton, PA, USA

problem #3

Feb 142021

Sierra 2500

  • 8,501 miles
The screen on my truck has gone blank several times and the volume on the radio goes super load and the only way to stop it seems to be to stop and turn off the truck, open the doors and re start truck. Today, I couldn't get my screen to go off in my truck when I turned it off, I tried turning off, restarting etc but to no avail. I'm at work now and fear that the battery will go dead before I get off work. I just had the truck at GMC 2/6/2021 and was told that their were no recalls. Also, note that when the screen kept going out I took it to the dealer and they said they had to reflash/reprogram it which took 5 hours.

- Las Vegas, NV, USA

problem #2

Jul 172020

Sierra 2500

  • miles
Part #19419266 tonneau was installed 07/16/2020 and leaks terrible in the rain

- St. Louis, MO, USA

problem #1

Feb 012020

Sierra 2500

  • 4,500 miles
The front park assist sensors on this truck do not operate as intended, or as on prior years or as on other vehicles. The sensors did not pick up parking bollards in front of a convenience store and resulted in a minor ding that cost over $1300 to repair. When bumper was repaired the service person said sensors were fixed, yet, to his surprise, we were able to inch up to a car directly intersecting the front of the car and it did not pick it up. I did a similar test with a brand new/unsold vehicle on dealer lot ind it failed to sense the large truck directly in front of it. This I believe can be a very dangerous safety issue as the truck hood sits very high impeding viability and a small person or pet can easily go undetected. These vehicles has also had numerous recalls including one for the possibility of the hood flying open while operating. I have sold the truck as all of these issues have devalued the vehicle, it remains unsafe and GM response has been less than favorable.

- New Egypt, NJ, USA