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2021 GMC Sierra 3500HD

Heavy-duty pickup
0 EPA-rated configurations
Data refreshed 2026-09-11
F
Safety Signal
58 / 100 from the NHTSA recall record
Recalls1 critical5
Complaintsowner reports to NHTSA20
Crash ratingNHTSA overall—
20262025202420232022202120202019201820172016
Active NHTSA advisory: park outside and away from structures until repaired. Check your VIN at nhtsa.gov/recalls and see the recall details below.

The 2021 GMC Sierra 3500HD is a heavy-duty pickup; vehicles over 8,500 lb GVWR are not certified for fuel economy by the EPA, so this page is built from NHTSA's recall, complaint and investigation records. NHTSA lists 5 recall campaigns for this model year, 1 rated critical, which gives it a Safety Signal grade of F. Owners have filed 20 complaints, most often about the power train.

Specs & fuel economy

Source: EPA fueleconomy.gov

No EPA fuel-economy record: the EPA does not certify vehicles over 8,500 lb GVWR. Recall, complaint and investigation data below come from NHTSA.

Factory warranty running out?

The 2021 GMC Sierra 3500HD is in the years where transmission, electronics and drivetrain repairs land on the owner. Compare extended-coverage quotes in about two minutes.

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Recalls (5)

Source: NHTSA recall database
○minor

Power Train

N242454440
463,295 vehicles
ProblemGeneral 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.RiskRear wheel lock-up can increase the risk of a crash.FixDealers 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.
NHTSA campaign 24V797000reported Oct 24, 2024General Motors, LLC
▲high

Latches/Locks/Linkages

N232426400
570,434 vehicles
ProblemGeneral 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.RiskAn 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.FixOwners 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.
NHTSA campaign 24V060000reported Feb 1, 2024General Motors, LLC
!critical

Service Brakes, Hydraulic

N212349181
Park outside3,241 vehicles
ProblemGeneral Motors, LLC (GM) is recalling certain 2021-2022 Chevrolet Silverado 2500, Silverado 3500, GMC Sierra 2500, and Sierra 3500 vehicles with electronic brake control modules (EBCM) replaced during vehicle assembly. The bolts that attach the brake pressure modulator valve (BPMV) assembly may not be properly tightened, which could fail to seal the two sub-assemblies and allow water intrusion.RiskWater in the BPMV may cause an electrical short circuit and increase the risk of fire.FixOwners are advised to park outside and away from other structures until the recall repair is completed. Dealers will replace the BPMV assembly, free of charge. Owner notification letters were mailed on October 20, 2021. 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 N212349181.
NHTSA campaign 21V758000reported Sep 29, 2021General Motors, LLC
▲high

Seat Belts

N202322230
470 vehicles
ProblemGeneral Motors, LLC (GM) is recalling certain 2020 Chevrolet Bolt EV and 2021 GMC Canyon and Sierra 1500, 2500 and 3500, Yukon, Yukon XL, Cadillac Escalade and Escalade ESV and Chevrolet Blazer, Camaro, Colorado, Equinox, Silverado 1500, 2500 and 3500, Suburban and Tahoe vehicles. Incorrect bolts may have been used at one or more fastening locations to secure the seat belts to the vehicle. If an incorrect bolt was used, the seat belt may not be properly attached to the vehicle.RiskIf a seat belt assembly is not properly attached to the vehicle, the seat belt may not properly restrain an occupant in the event of a crash, increasing the risk of injury.FixGM will notify owners, and dealers will replace the suspect bolts, free of charge. The recall began January 29, 2021. Owners may contact GMC customer service at 1-800-462-8785, Cadillac customer service at 1-800-458-8006, or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N202322230.
NHTSA campaign 20V811000reported Dec 23, 2020General Motors, LLC
▲high

Seat Belts

N202314670
624,216 vehicles
ProblemGeneral 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.RiskIf a seat-belt bracket is not secured, the seat belt may not properly restrain an occupant in the front-row center seat position, increasing the risk of injury in a crash.FixGM 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.
NHTSA campaign 20V792000reported Dec 17, 2020General Motors, LLC

NHTSA defect investigations

Air Bags:Srs Malfunction Warning Lamp/Light — Air Bag Malfunction closed

On April 9, 2021, the Office of Defects Investigations (ODI) opened PE21-010 to investigate instances of air bag malfunction indicator light (MIL) illumination and potential for frontal air bag non-deployment in several vehicles manufactured by General Motors (GM). The vehicles included model year (MY) 2020 through 2021 CT4 and CT5 passenger cars, Sierra and Silverado trucks (1500/2500/3500 models), XT4 and MY 2021 Escalade, Suburban, Tahoe, Yukon SUVs.Technical Service Bulletin (TSB) 21-NA-005, issued in March 2021, addresses air bag MIL illumination with diagnostic trouble codes (DTCs) B0001-1B or B0012-0D. It cites rust particles in the connection terminal interface of the driver air bag

Opened Apr 9, 2021 · closed Aug 24, 2023 · action PE21010

Owner complaints

Source: NHTSA complaint database
20complaints filed

0 involved a crash · 0 a fire · 0 injuries · 0 deaths reported

Filed per year: 2021: 2 · 2022: 5 · 2023: 1 · 2024: 3 · 2025: 8 · 2026: 1

Most-cited components

Power Train7
Service Brakes5
Electrical System4
Engine3
Unspecified3
Fuel/Propulsion System2

What owners describe

“The contact filed the complaint on behalf of the owner of a 2021 GMC Sierra 3500. The contact stated that while the vehicle owner was driving at an undisclosed speed, the driver noticed that the rear wheels were attempting to lockup. The contact stated that the failure was noticeable while driving forward and while rev…”Jun 12, 2026 · Service Brakes · NHTSA owner report
“During takeoff the transmission acted as if it was in neutral while I was crossing traffic luckily, the semi truck that was coming towards me was able to stop. I had the vehicle towed to a shop. After the vehicle was towed to the shop the transmission acted normal when the mechanic searched the VIN number. There was a …”Nov 24, 2025 · Power Train · NHTSA owner report
“The contact owns a 2021 GMC Sierra 3500. The contact stated that while his wife had the vehicle idling with the rear defroster activated, shortly afterwards, she observed smoke coming from the plastic on the rear sliding window. After a visual inspection, the contact's wife observed that the plastic was melting, prompt…”Sep 8, 2025 · Electrical System · NHTSA owner report

Complaint counts are raw owner reports to NHTSA, not verified defects, and scale with how many were sold. Use them to spot patterns, not to rank.

Crash ratings

Source: NHTSA NCAP

NHTSA has not published 5-Star crash ratings for this model year.

Compare the 2021 Sierra 3500HD with

2021 Chevrolet Silverado 2500HD →2021 Chevrolet Silverado 3500HD →

Other Sierra 3500HD model years

B

2026 GMC Sierra 3500HD

2 recalls · 4 complaints

A

2025 GMC Sierra 3500HD

1 recalls · 16 complaints

C

2024 GMC Sierra 3500HD

3 recalls · 44 complaints

A

2023 GMC Sierra 3500HD

1 recalls · 28 complaints

C

2022 GMC Sierra 3500HD

3 recalls · 31 complaints

F

2020 GMC Sierra 3500HD

8 recalls · 51 complaints

F

2019 GMC Sierra 3500HD

7 recalls · 13 complaints

F

2018 GMC Sierra 3500HD

6 recalls · 14 complaints

F

2017 GMC Sierra 3500HD

7 recalls · 13 complaints

F

2016 GMC Sierra 3500HD

6 recalls · 19 complaints

Sources & method

Safety Signal starts every model-year at 100 and subtracts points per open NHTSA recall campaign by severity: critical 15 (fire risk, park-outside or do-not-drive advisories), high 8 (brakes, steering, airbags, loss of drive power, structure, battery), moderate 6, minor 3 (software, labels, lighting fixed by an update). Floor 35. A ≥ 90, B ≥ 80, C ≥ 70, D ≥ 60, otherwise F. Complaint counts and NHTSA crash ratings are shown separately and are not blended into the grade.

EPA figures come from fueleconomy.gov vehicle records. Recalls, complaints, investigations and crash ratings come from NHTSA's public flat files, refreshed weekly.

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