This informational bulletin provides information on the Low Cab Forward trucks and the Alpine Radio Exchange Program.
full bulletin at NHTSA ↗2020 Chevrolet 3500 electrical problems
severe Owners of the 2020 Chevrolet 3500 have filed 5 NHTSA complaints about the electrical at roughly $850 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See electrical across all vehicles →
| Model year | electrical complaints |
|---|---|
| 2016 3500 | 5 |
| 2020 3500 (this page) | 5 |
| 2022 3500 | 4 |
When does it fail?
Of the 5 electrical complaints filed for the 2020 Chevrolet 3500, here's the actual mileage breakdown — failures cluster heaviest at 25,000-50,000 mi.
Each bar shows the share of total complaints filed at that mileage range. Peak failure window highlighted. Some owners report problems earlier; some make it well past 150,000 miles symptom-free. Maintenance habits and driving conditions shift the curve as much as mileage alone.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering electrical on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
The intent of this service bulletin is to identify aftermarket ALDL or DLC interface devices as potential sources for causing multiple customer concerns that do not have other diagnostic methods to identify them.
full bulletin at NHTSA ↗This service bulletin provides information to diagnose batteries that have set for a long period of time and/or cold weather climates and testing those batteries.
full bulletin at NHTSA ↗This bulletin advises the dealers to maintain the vehicle stock on hand by doing a full inspection on the vehicles before being sold (prepping) to the customer.
full bulletin at NHTSA ↗This service bulletin provides information on the Transport Mode Feature, also known as Logistics mode, which is used to increase the 12V Battery stand time of the vehicle during transit and or long period of stand time at the dealerships.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
What owners are reporting 5 most recent
The contact owns a 2020 Chevrolet Silverado 3500. The contact stated that while depressing the brake pedal, the tailgate brake light failed to illuminate. In addition, the contact stated that while a trailer was hitched to the vehicle, the message "Check Trailer Connection" was displayed, and other unknown warning lights were illuminated. The vehicle was taken to a local dealer where it was…
The blower motor for the HVAC system caught fire.
The contact owns a 2020 Chevrolet Silverado 3500. The contact stated that while hauling a 2020 Heartland Cyclone, the trailer brakes unexpectedly deactivated. The contact stated that the trailer brake was disconnected, and the warning light to check the trailer winch was illuminated. The vehicle was taken to the dealer, who was unable to determine the cause of failure. The vehicle was not…
I purchased a certified pre-owned 2020 Chevy Silverado 3500HD (6.6 Gas) November 2021. Within the next few weeks, I noticed brake squeaking that kept getting worse and the truck braking system would not stop like the 2500 I had traded in when I purchased the 3500HD. I had to adjust the trailer brake gain control up to as high as 9 or 9.5, should not have to adjust that high. I had trouble…
GM recall N2123544170 DPF regeneration temperature /DEF heater for cold weather operation to keep def from freezing and also for thawing frozen def...dealer to replace def tank and internal heating element...dealer was unable to give a time line for replacement parts needed to fix truck.(parts are back ordered)So truck ECM=electonic control module.throws trouble code to reduce engine power that…
Common questions
How serious is the electrical problem on the 2020 Chevrolet 3500?
It's a meaningful issue. 5 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $850.
At what mileage does the electrical typically fail?
Based on the 5 complaints filed, electrical issues most often appear around 39,000 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $850 for electrical repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to electrical?
No active recalls currently cover electrical issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.