2021 GMC Sierra 3500

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2021 GMC Sierra 3500
RENDERED 2026-08-02T11:13:01.565Z

Only 20 complaints on file — too few for a fair verdict.

This verdict reflects complaint volume compared to this model's typical year. Recalls and safety issues below apply regardless of the verdict — always check them.

Only 20 complaints on file — too few for a fair verdict. The data below is complete but unranked.

How is this computed?

COMPLAINTS PER YEAR

Complaints per year, GMC Sierra 3500 Bar chart of distinct NHTSA complaints filed per model year, 2021 highlighted. 1996: 1 complaints 1996 1997: 10 complaints 1998: 12 complaints 1999: 19 complaints 2000: 26 complaints 2000 2001: 36 complaints 2002: 20 complaints 2003: 7 complaints 2004: 24 complaints 2004 2005: 24 complaints 2006: 11 complaints 2007: 16 complaints 2008: 24 complaints 2008 2009: 5 complaints 2010: 2 complaints 2011: 20 complaints 2012: 9 complaints 2012 2013: 14 complaints 2014: 7 complaints 2015: 30 complaints 2016: 19 complaints 2016 2017: 13 complaints 2018: 14 complaints 2019: 12 complaints 2020: 51 complaints 2020 2021: 20 complaints 2021 2022: 27 complaints 2023: 26 complaints 2024: 40 complaints 2024 2025: 16 complaints 2026: 1 complaints 2026
2021: 20 complaints
View as data table
YearComplaints
19961
199710
199812
199919
200026
200136
200220
20037
200424
200524
200611
200716
200824
20095
20102
201120
20129
201314
20147
201530
201619
201713
201814
201912
202051
202120
202227
202326
202440
202516
20261

KNOWN PROBLEM AREAS

Only 20 complaints on file for this model year -- too few to rank by share. Raw counts only, below.

POWER TRAIN

7 of 20 total reports mention: power train.

Show complaint excerpts

While driving 55mph on a 2 lane road, pulling a 5th wheel camper, the truck transmission downshifted by itself to a low gear. This caused a scary and immediate deceleration from 55 to 25mph.

NHTSA ODI report, 20241001

SERVICE BRAKES

5 of 20 total reports mention: service brakes.

Show complaint excerpts

When starting the vehicle, I got a message to service the parking brake (this is the second time I’ve had this warning appear in the 21,000 miles I’ve owned it, first was approximately 5,000 miles ago).

NHTSA ODI report, 20240419

The vehicle recently had a recall repaired at the dealership. I subsequently took delivery on it as a BRAND NEW UNIT, and the brakes are extremely soft; to the point where I must depress the pedal to the floor to get it stopped even at slow speeds.

NHTSA ODI report, 20211026

Trailer brake wiring connection continually disconnectsthen reconnects some time later. Some periods of up to 10 minutes without having trailer braking power. Major safety issue when toeing fifth wheel trailer.

NHTSA ODI report, 20210610

ELECTRICAL SYSTEM

4 of 20 total reports mention: electrical system.

Show complaint excerpts

Trailer brake wiring connection continually disconnectsthen reconnects some time later. Some periods of up to 10 minutes without having trailer braking power. Major safety issue when toeing fifth wheel trailer.

NHTSA ODI report, 20210610

ENGINE

3 of 20 total reports mention: engine.

Show complaint excerpts

Multiple instances of diesel engine emissions system parts and software failure.

NHTSA ODI report, 20241101

FUEL/PROPULSION SYSTEM

2 of 20 total reports mention: fuel/propulsion system.

SAFETY TIMELINE

R 20210126 — 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.

Remedy: 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.

Campaign 20V792000 — check if this car was fixed

R 20210129 — seat belts

General 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...

Remedy: GM will notify owners, and dealers will replace the suspect bolts, free of charge. The recall began January 29, 2021.

Campaign 20V811000 — check if this car was fixed

I 20210409 — PE (closed 20230824)

Air Bag Malfunction

R 20211020 — service brakes, hydraulic

General 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.

Remedy: Owners 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.

Campaign 21V758000 — check if this car was fixed

R 20240517 — 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.

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.

Campaign 24V060000 — check if this car was fixed

R 20241212 — 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...

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.

Campaign 24V797000 — check if this car was fixed

BUY-SMART CHECKLIST

2021 GMC Sierra 3500 — pre-purchase inspection

  • Test/inspect for power train issues (7 reports on file for this year).
  • Test/inspect for service brakes issues (5 reports on file for this year).
  • Test/inspect for electrical system issues (4 reports on file for this year).
  • Verify recall 20V792000 (seat belts) has been completed.
  • Verify recall 20V811000 (seat belts) has been completed.
  • Verify recall 21V758000 (service brakes, hydraulic) has been completed.
  • Verify recall 24V060000 (latches/locks/linkages) has been completed.
  • Verify recall 24V797000 (power train) has been completed.

FAQ

Is the 2021 GMC Sierra 3500 reliable?

There isn't enough NHTSA complaint data on file yet to give this model year a verdict.

What are the most common problems with the 2021 GMC Sierra 3500?

The most-reported component is power train, accounting for 35% of complaints on file.

How many recalls does the 2021 GMC Sierra 3500 have?

5 recalls on file for this model year.

Data updated 2026-07-11 · Complaints are unverified owner reports filed with NHTSA, not independently verified defects. Methodology.