This service bulletin provides information on the harmful effects of ethylene glycol in transmission fluid.
full bulletin at NHTSA ↗2020 Chevrolet 3500 powertrain problems
severe Owners of the 2020 Chevrolet 3500 have filed 9 NHTSA complaints about the powertrain at roughly $2,500 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See powertrain across all vehicles →
| Model year | powertrain complaints |
|---|---|
| 2016 3500 | 3 |
| 2020 3500 (this page) | 9 |
| 2022 3500 | 3 |
| 2023 3500 | 9 |
When does it fail?
Of the 9 powertrain 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.
Powertrain accounts for 32% of every owner complaint on file for this vehicle — the dominant problem area across 4 categories tracked.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering powertrain 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.
This informational bulletin explains Unscheduled Supplemental Services and the importance of GM Simplified Maintenance Schedules.
full bulletin at NHTSA ↗This technical bulletin provides a procedure for the techs to replace the forward check ball and separator plate if found the cause of the customers concern of No Forward Gear When Shifting from Park to Drive and/or Reverse to Drive.
full bulletin at NHTSA ↗This technical bulletin provides a procedure for the techs to replace the forward check ball and separator plate if found the cause of the customers concern of No Forward Gear When Shifting from Park to Drive and/or Reverse to Drive.
full bulletin at NHTSA ↗GM is receiving damaged (cracked or broken) transmission cores returned to the reman facilities. The damage is being caused either in the removal process by the technician, or inadequate packaging or shipping. This bulletin advises the dealers to be more careful not to damage the transmissions during removal and to package the core properly for return.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
What owners are reporting 6 most recent
Dealership told me the throttle body failed in my transmission. I wanted it completely torn down to find the actual point of failure since it did represent the current recall on the truck that hadn't been done because the part isn't yet available. The transmission has been replaced for almost $10,000.00
2nd time I’ve had to replace def heater and tank. Truck goes into limp mode and limits the speed leaving a person stranded.
Transmission lock up traveling 45 miles an hour while acceleration up modest uphill grade pulling a 3000 pound trailer. The lockup was severe enough to cause passengers to lunge forward with seatbelt engagement. There was no loss of control of the vehicle; however, we did stop the vehicle to inspect it with no damage observed. We expected to see some. This event would have caused a likely loss of…
The contact owns a 2020 Chevrolet Silverado 3500. The contact stated that the check engine warning light was illuminated. Additionally, the vehicle later failed to start and became undrivable. The dealer was notified of the failure and an appointment was scheduled for diagnostic testing and for the manufacturer internal recall repairs. The vehicle was not diagnosed or repaired. Additionally, the…
The contact owns a 2020 Chevrolet Silverado 3500. The contact stated while driving 65 MPH, the rear wheels locked-up. The contact was able to pull over to the side of the road. The contact resumed driving, but the vehicle was driving roughly, and the failure recurred while driving 30 MPH. The check engine warning light, the electronic stability control warning light, and other unknown warning…
I recieved a recall notice from Chevrolet stating they needed to install a software update to the truck which will warn if a potential rear wheel lock up is about to occur due to faulty transmission valve body- which was stated that they do not have a fix for. After software update was installed- I was driving about 35 mile per hour on the trip home, and the truck abruptly downshifted very hard,…
Common questions
How serious is the powertrain problem on the 2020 Chevrolet 3500?
It's a meaningful issue. 9 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $2,500.
At what mileage does the powertrain typically fail?
Based on the 9 complaints filed, powertrain issues most often appear around 82,000 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 $2,500 for powertrain 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 powertrain?
No active recalls currently cover powertrain 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.