The Lemon IndexAll cars · GMC · GMC Sierra 2500HD/3500HD
2020 GMC Sierra 2500HD/3500HD problems, engines and recalls.
Owners filed 131 complaints with the government about the 2020 GMC Sierra 2500HD/3500HD, most often about transmission & drivetrain (34%).
Which engine is in it
130 of the 131 complaints have a VIN we could decode, which tells us the engine.
| Engine | Share | Complaints | What they name most |
|---|---|---|---|
| 6.6 Duramax L5P diesel | 89% | 116 | transmission & drivetrain 33%, brakes 16%, electrical 16% |
| 6.6 V8 gas (L8T) | 11% | 14 | too few to split |
Each diesel's page: Duramax L5P.
Nearby model years
What owners complain about
Share of this year's complaints that name each area.
When problems show up
Half of the owners who gave a mileage reported the problem between 6,300 and 108,000 miles; the middle report was at 31,800 miles (36 complaints with a mileage).
How serious
| Crashes | Fires | Injury reports | Death reports | Towed |
|---|---|---|---|---|
| 5 | 6 | 2 | 0 | 11 |
As reported by owners to NHTSA, not verified.
In owners' words
My rear spoiler roof area leaks. This is something GM knows about and has sent out memos to dealers. To fix this it’s around $1000. I think GM should fix a problem they have been well aware of for sometime.
2020 GMC Sierra 2500HD/3500HD owner · NHTSA complaint 11769733
When I try to start my truck it comes up as service trailer brake control module and it has caused my truck battery to drain so I cant even crank my truck up.
2020 GMC Sierra 2500HD/3500HD owner · NHTSA complaint 11762323
A couple times I heard loud clanking coming from rear brakes. One time in particular I was trying to stop and it felt line someone had ran into my truck but must have been the rear wheel locking up
2020 GMC Sierra 2500HD/3500HD owner · NHTSA complaint 11718162
Recalls 9
26V083000 Feb 2026 Power Train
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.
Fix. 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 Feb
24V797000 Oct 2024 Power Train
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.
Fix. 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
24V060000 Feb 2024 Latches/Locks/Linkages
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.
Fix. 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.
21V578000 Jul 2021 Tires
General Motors, LLC. (GM) is recalling certain 2020-2021 Chevrolet Silverado 2500 and GMC Sierra 2500 vehicles equipped with a 17" spare tire (RPO ZHQ or ZXT) and either the 20" accessory road tire (RPO REM) or the 18" accessory road tire (RPO Q2V). Operating the spare tire with other 20" or 18" tires can prevent the Anti-Lock Braking System (ABS) from engaging.
Fix. Dealers will provide the appropriate spare tire and apply a new spare tire information label, free of charge. Owner notification letters were mailed on October 18, 2021. Owners may contact Chevrolet customer service at 1-800-222-1020; GMC customer service at 1-800-462-8782. GM's number for this recall is N212329780.
20V792000 Dec 2020 Seat Belts
General Motors, LLC (GM) is recalling certain 2019-2021 Chevrolet Silverado 1500 and GMC Sierra 1500, 2021 Chevrolet Suburban and Tahoe and GMC Yukon XL and 2020-2021 Chevrolet Silverado 2500 and 3500 and GMC Sierra 2500 and 3500 vehicles. The seat belt brackets may not be secured to the seat frame in the front-row center seating position.
Fix. GM will notify owners, and dealers will inspect left-side and right-side front-row center seat-belt bracket attachments and reassemble it correctly as necessary, free of charge. The recall began January 26, 2021. Owners may contact GMC customer service at 1-800-462-8782, Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N202314670.
20V446000 Jul 2020 Air Bags
General Motors, LLC. (GM) is recalling certain 2020 Buick Enclave, Cadillac XT5 and XT6, Chevrolet Blazer, Silverado 1500, 2500 and 3500 and Traverse and GMC Acadia and Sierra 1500, 2500 and 3500 vehicles. The diffuser component of the Roof-Rail Air Bag (RRAB) inflator may not have been properly crimped to the inflator and could separate from the inflator during air bag deployment.
Fix. GM will notify owners, and dealers will replace the suspect RRAB modules, free of charge. The recall began September 3, 2020. Owners may contact Chevrolet customer service at 1-800-630-2438, Cadillac customer service at 1-800-333-4223, or Buick customer service at 1-800-521-7300. GM's number for this recall is N202305380.
20V324000 Jun 2020 Structure
General Motors LLC (GM) is recalling certain 2020 Chevrolet Silverado 2500 and 3500 and GMC Sierra 2500 and 3500 vehicles previously recalled under 20V-142. Some of the vehicles in 20V-324 were not part of Recall 20V-142 but received defect parts during another service (typically during collision repair). The hood-latch striker wires on replacement hoods installed for Safety Recall 20V-142 may not have been heat-treated properly, possibly causing them to fracture.
Fix. GM will notify owners, and dealers will replace the hood assembly, free of charge. For hoods sold over the counter, dealers will contact customers with instructions for hood replacement. The recall began July 7, 2020. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-888-988-7267. GM's number for this recall is N202306490.
20V142000 Mar 2020 Latches/Locks/Linkages
General Motors LLC (GM) is recalling certain 2020 Chevrolet Silverado 2500 and 3500 and GMC Sierra 2500 and 3500 vehicles. The hood-latch striker wires may not have been heat-treated properly, possibly causing them to fracture.
Fix. GM will notify owners, and dealers will replace the hood assembly, free of charge. The recall began April 13, 2020. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-888-988-7267. GM's number for this recall is N192284960.
19V814000 Nov 2019 Seat Belts
General Motors LLC (GM) is recalling certain 2019-2020 Chevrolet Silverado 1500 and GMC Sierra 1500, and 2020 Silverado 2500, Silverado 3500, Sierra 2500, and Sierra 3500 vehicles equipped with carpet floor covering. When the front seat belt pretensioners deploy, hot gas may vent through an opening in the pretensioner bracket, possibly igniting the carpet.
Fix. GM will notify owners, and dealers will close off the opening in the pretensioner bracket, free of charge. The recall began December 13, 2019. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-888-988-7267. GM's number for this recall is N192270600.
NHTSA recalls for this model year under every name these trucks are filed under. A recall that names an engine applies only to trucks with it. Free at any dealer: check the VIN.
Quick answers
Is the 2020 Sierra HD reliable?
We can't score it per truck (heavy-duty sales aren't reported apart from the half-ton). Owners filed 131 complaints about it, most often about transmission & drivetrain (34% of them). Compare the diesel generations on their engine pages.
What engine does the 2020 Sierra HD have?
By the VINs in owner complaints: 6.6 Duramax L5P diesel (89%), 6.6 V8 gas (L8T) (11%).
How many recalls does the 2020 GMC Sierra 2500HD/3500HD have?
9. Recall repairs are free at any dealer; check the truck's VIN at nhtsa.gov/recalls.
The whole-line score for 2020, mostly half-tons: 2020 GMC Sierra.
No Lemon Index score: automakers report heavy-duty pickup sales together with the half-ton (one F-Series, Ram or Silverado number), so there is no honest per-truck denominator. These are counts and shares of owner complaints, not failure rates. Complaints: NHTSA owner complaints filed under the truck's 2500/3500 (F-250/F-350) names, all years filed, one per complaint number. Engine: decoded from the complaint's VIN (position 8 is the engine code) with NHTSA's vPIC decoder. Complaints filed as just “Silverado” or “Sierra” are left out (they mix 1500s and HDs). Older trucks have had more years to collect complaints, and popular years draw more because more were sold.
Updated · Free to use with credit: Source: The Lemon Index (lemonindex.com)
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