2020 GMC Sierra 3500 Reliability Data: Problems & Recalls
Avoid The 2020 GMC Sierra 3500 has a complaint index of 95, ranking 2nd-worst of 21 model years, with 51 complaints and 8 recalls. Transmission & Powertrain problems account for 37% of complaints, giving it an Avoid verdict relative to other Sierra 3500 years.
Based on NHTSA complaints per model-year, not a reliability rating. Methodology
YearToAvoid Scorecard
- Complaint Index
- 95/100
- #2 of 21 Sierra 3500 years
- Verdict
- Avoid
- vs. other years of this model
- Complaints
- 51
- unique NHTSA reports
- Recalls
- 8
- distinct NHTSA campaigns
- Crashes
- 4
- reported in complaints
- Fires
- 2
- Injuries
- 4
- Top issue
- Transmission & Powertrain
Top 2020 GMC Sierra 3500 problems
Share of this year’s NHTSA complaints by component group. Groups with 15+ complaints have their own page.
- Transmission & Powertrain19 (37%)
- Electrical System10 (20%)
- Brakes7 (14%)
- Engine7 (14%)
- Fuel System6 (12%)
- Other6 (12%)
- Structure & Body6 (12%)
- Suspension, Wheels & Tires5 (10%)
- Visibility & Wipers2 (4%)
- Airbags1 (2%)
A complaint can list more than one component, so shares add up to more than 100%. Shares are % of complaints.
What owners report
- Rear differential seizes at highway speed, in one case at a median mileage of 108,000 miles, causing loss of control while towing.
- Transmission suddenly bangs and locks the rear brakes at around 50 mph, forcing an abrupt, unplanned stop.
- Acceleration attempts trigger violent skidding and loss of control at highway speeds, reportedly recurring within a short span.
- Trailer brake system disengages while the dash lights up and power is reduced, sometimes several times per trip.
- Steering wheel shakes or shimmies above 50 mph and persists despite repeated dealer repair attempts.
- Vehicle develops a progressive delay in starting that eventually leads to a complete no-start condition tied to battery failure.
2020 GMC Sierra 3500 recalls
8 NHTSA recall campaigns list this model year.
- NHTSA 26V083000Feb 12, 2026Transmission & Powertrain1,055 vehicles
Power train:automatic transmission:fluid/lubricant:valves/valve body
General Motors, LLC is recalling certain 2020 Chevrolet Silverado 2500, 3500, GMC Sierra 2500, 3500, and 2020-2022 Chevrolet Silverado 1500 and GMC Sierra 1500 vehicles that may have been repaired incorrectly under recall 24V797. The transmission control valve may fail and cause the rear wheels to lock up.
Risk: Rear wheel lock up increases the risk of a crash.
Remedy: Dealers will inspect the vehicles and update the transmission control software, free of charge. Owner notification letters were mailed March 6, 2026. Owners may contact GMC customer service at 1-800-462-8782 or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N252516560. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov on February 12, 2026.
- NHTSA 24V797000Oct 24, 2024Transmission & Powertrain463,295 vehicles
Power train:automatic transmission:fluid/lubricant:valves/valve body
General Motors, LLC (GM) is recalling certain 2020-2022 Chevrolet Silverado 1500, 2500, 3500, GMC Sierra 1500, 2500, 3500, 2021 Cadillac Escalade, Escalade ESV, Chevrolet Tahoe, Suburban, GMC Yukon, and Yukon XL vehicles equipped with diesel engines. The transmission control valve may fail and cause the rear wheels to lock-up.
Risk: Rear wheel lock-up can increase the risk of a crash.
Remedy: Dealers will install new transmission control module software, free of charge. GM will provide a special coverage program to cover the repair of transmissions that are identified by the remedy software as containing a defective control valve. Owner notification letters were mailed December 12, 2024. Owners may contact GM customer service at 1-888-988-7267, Cadillac customer service at 1-800-458-8006, GMC customer service at GMC 1-800-462-8782 or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N242454440.
- NHTSA 24V060000Feb 1, 2024Structure & Body570,434 vehicles
Latches/locks/linkages:tailgate:latch
General Motors, LLC (GM) is recalling certain 2020-2024 Chevrolet Silverado 2500, 3500, GMC Sierra 2500 and 3500 vehicles equipped with power-unlatching tailgates. The tailgate's electronic gate-release switch may short circuit due to water intrusion, which can result in the tailgate inadvertently unlatching while the vehicle is in park.
Risk: An unlatched tailgate may open while driving and result in a loss of unsecured cargo, creating a road hazard and increasing the risk of a crash.
Remedy: Owners are advised to check that the tailgate is closed and latched before driving. Dealers will replace the exterior touchpad switch assemblies, free of charge. Owner notification letters were mailed May 17, 2024. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-800-462-8782. GM's number for this recall is N232426400.
2020 compared with other Sierra 3500 years
Frequently asked questions
- Is the 2020 GMC Sierra 3500 reliable?
- Based on NHTSA owner complaints and recalls, the 2020 Sierra 3500 ranks 2nd-worst out of 21 model years for this model, with a complaint index of 95 and 8 recall campaigns.
- What are the most common problems with the 2020 GMC Sierra 3500?
- Transmission & Powertrain issues make up 37% of complaints (19 of 51), followed by Electrical System problems at 20% and Brakes at 14%.
- Does the 2020 GMC Sierra 3500 have transmission recalls?
- Yes. NHTSA lists two transmission-related recalls (24V797000 and 26V083000) covering transmission control module software, along with other recalls for hood latches, airbags, seat belts, and tailgates.
- At what mileage do transmission problems appear on the 2020 Sierra 3500?
- NHTSA complaint data shows a median mileage at failure of 108,000 miles for Transmission & Powertrain complaints on this year.
- How does the 2020 Sierra 3500 compare to other years?
- Its complaint index of 95 is close to the worst year, 2024, at 100, while years like 2012, 2013, and 2014 rate Best with complaint indexes of 10, 20, and 15 respectively.