2021 Chevrolet Silverado 3500 electrical system problems
11 owner complaints filed with NHTSA name the electrical system on the 2021 Chevrolet Silverado 3500 — 29% of all complaints for this model year.
What owners report
“Water entered tailgate through drainage hole in tailgate cap. The water then dripped on the tailgate switch causing it to short out. This short circuit caused my tailgate to open and close randomly without pressing any switches or buttons or key fobs. May tailgate has a small ding it it now from…”
filed Apr 29, 2026
“My 2021 chevy 3500hd diesel had the engine light come on and the service emissions system popped up in the info screen. It said in so many miles speed would be limited. I took it to the dealer and they said the def tank would need replaced because the tank wiring connector overheated and would cost…”
filed Feb 8, 2026
Verbatim excerpts from complaints filed with NHTSA. Reports are not independently verified.
Electrical System problems in other Silverado 3500 years
| Year | Reports | Share |
|---|---|---|
| 2024 Silverado 3500 | 18 | 38% |
| 2022 Silverado 3500 | 5 | 19% |
| 2020 Silverado 3500 | 5 | 13% |
| 2019 Silverado 3500 | 5 | 24% |
| 2016 Silverado 3500 | 6 | 12% |
| 2015 Silverado 3500 | 16 | 31% |
| 2013 Silverado 3500 | 4 | 15% |
| 2012 Silverado 3500 | 2 | 9% |
| 2011 Silverado 3500 | 2 | 7% |
| 2008 Silverado 3500 | 6 | 19% |
| 2007 Silverado 3500 | 2 | 5% |
| 2006 Silverado 3500 | 3 | 6% |
Other reported problem areas on the 2021 Chevrolet Silverado 3500
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.