2020 GMC Sierra 2500 electrical system problems
12 owner complaints filed with NHTSA name the electrical system on the 2020 GMC Sierra 2500 — 16% of all complaints for this model year.
What owners report
“The main tailgate will not go down or function properly and it says online there is a national recall for this, but does not come up when I search my vehicle. When I turn on my left turn signal the brights flash for no reason and this is a known major issue with the vehicles as well. The trucks…”
filed Dec 20, 2025
“The rear defroster massively overheated. It started heavily smoking and eventually exploded the rear windows. Only warning sign was the smoke which we noticed quickly because the windows were up. Had the windows been down we might not have noticed before a fire started. I'm taking it to a…”
filed Nov 24, 2025
Verbatim excerpts from complaints filed with NHTSA. Reports are not independently verified.
Electrical System problems in other Sierra 2500 years
| Year | Reports | Share |
|---|---|---|
| 2024 Sierra 2500 | 31 | 32% |
| 2023 Sierra 2500 | 5 | 17% |
| 2022 Sierra 2500 | 12 | 29% |
| 2021 Sierra 2500 | 6 | 12% |
| 2019 Sierra 2500 | 9 | 28% |
| 2018 Sierra 2500 | 7 | 20% |
| 2017 Sierra 2500 | 6 | 16% |
| 2016 Sierra 2500 | 9 | 15% |
| 2015 Sierra 2500 | 11 | 12% |
| 2014 Sierra 2500 | 4 | 13% |
| 2013 Sierra 2500 | 3 | 7% |
| 2012 Sierra 2500 | 4 | 13% |
Other reported problem areas on the 2020 GMC Sierra 2500
Counts are unique NHTSA complaints naming this component group. Complaints are unverified owner reports; mileage is computed only from complaints that included a usable odometer reading.