83+ 2021 GMC Sierra 3500 HD Suspension & Steering AT4 Parts

AT4 · Suspension & Steering (78 products)

Exact-fit parts for the 2021 GMC Sierra 3500 HD AT4.

Cognito

Part # 110-90771

Confirmed Fit

Cognito 20-24 Chevy/GMC Silverado/Sierra 2500/3500 HD 2WD/4WD Torsion Bar Keys

$143.31

Cognito

Part # 110-90952

Confirmed Fit

Cognito 20-24 Chev Silv/Sierra 2500/3500HD SM Series LDG Traction Bar Kit - For 5-9in Rear Lift

$1791.95

Firestone

Part # 2158

Confirmed Fit

Firestone Level Command II Standard Duty Single Analog Air Compressor System Kit (WR17602158)

$402.16

Tuff Country

Part # 10958

Confirmed Fit

Tuff Country 20-23 Chevy Silverado GMC Sierra 2500HD/3500HD Ball Joint Upper Control Arms

$731.51

Firestone

Part # 2709

Confirmed Fit

Firestone Ride-Rite RED Label Air Spring Kit Rear 2020 Chevrolet/GMC 2500/3500 2WD/4WD (W217602709)

$800.43

SPC Performance

Part # 86376

Confirmed Fit

SPC Performance 11+ Chevy/GMC 2500HD / 3500HD Upper Camber/Caster Kit

$71.09

Wehrli

Part # WCF100831

Confirmed Fit

Wehrli 20-24 Chevrolet Duramax Traction Bar Install Kit

$310.08

Timbren

Part # GMRTT35D

Confirmed Fit

Timbren 2011 Chevrolet Silverado 2500 HD Rear Suspension Enhancement System

$398.07

Air Lift

Part # 88341

Confirmed Fit

Air Lift Loadlifter 5000 Ultimate Rear Air Spring Kit for 2020+ Chevrolet Silverado 2500/3500

$732.99

Fabtech

Part # FTSBK21

Confirmed Fit

Fabtech 2in Rear Leaf Spring Block Kit - 3/4in Pin

$57.87

Timbren

Part # GMRCK25D

Confirmed Fit

Timbren 2011 Chevrolet Silverado 2500 HD Rear Suspension Enhancement System

$269.36

Timbren

Part # GMFK25D

Confirmed Fit

Timbren 2011 Chevrolet Silverado 2500 HD Front Suspension Enhancement System

$269.36

Body Armor 4x4

Part # 504014-GM

Confirmed Fit

Body Armor 4x4 2020+ GMC/Chevy 2500HD/3500HD 4WD 1.5in-2in Key and Shock Extender

$138.00

Fabtech

Part # FTS71006

Confirmed Fit

Fabtech 6in Driver & Passenger Tie Rod Assembly Kit

$408.79

Hellwig

Part # 7328

Confirmed Fit

Hellwig 20-22 Chevrolet Silverado 2500 HD Solid Heat Treated Chromoly 1-5/16in Big Wig Rear Sway Bar

$798.84

Hellwig

Part # 7782

Confirmed Fit

Hellwig 20-22 Chevrolet Silverado 2500/3500 HD 2/4WD Solid Chromoly 1-1/4in Rear Sway Bar

$771.75

Hellwig

Part # 3518

Confirmed Fit

Hellwig 20-21 Chevy Silv 3500 Load Pro- 3500lb Level LC 4 Leaf Stack Helper Spring w/o Mounting Kit

$507.56

Unity Automotive

Part # 2-211090-001

Confirmed Fit

Unity Automotive Front Shock Absorbers - 2-211090-001

$61.10

Firestone

Part # 2613

Confirmed Fit

Firestone Ride-Rite Air Helper Spring Kit Rear Chevy/GMC HD 2500/3500 (W217602613)

$702.68

Firestone

Part # 2873

Confirmed Fit

Firestone 11-24 Chevrolet Silverado 2500 2WD/4WD AIO Analog Ride-Rite All-In-One Kit (W217602873)

$1063.37

Frequently Asked Questions

Do these parts fit my 2021 GMC Sierra 3500 HD AT4?

This page groups parts listed for the 2021 GMC Sierra 3500 HD AT4. Some products fit every trim, while others depend on submodel, engine, drivetrain, or brake package. Use your trim in My Garage or the product page fitment check to confirm exact fit.

What suspension & steering options are available for my 2021 GMC Sierra 3500 HD AT4?

We offer a wide selection of suspension & steering parts for the 2021 GMC Sierra 3500 HD AT4. This page narrows the catalog to the year, make, and model; use your trim on product pages to confirm exact fit when a part only fits certain submodels.

What brands make parts for the 2021 GMC Sierra 3500 HD AT4?

We carry parts from trusted brands including Cognito, Firestone, Moog, Wehrli, and Fabtech, plus many more. Filter by brand to find your preferred manufacturer.

How fast do 2021 GMC Sierra 3500 HD AT4 parts ship?

Most in-stock items ship within 1-2 business days. Shipping rates are calculated at checkout based on your location.

What warranty do your 2021 GMC Sierra 3500 HD AT4 parts come with?

Warranty coverage varies by manufacturer but typically ranges from 1 year to lifetime. Each product page includes specific warranty information from the manufacturer.

2021 GMC Sierra 3500 HD(2,276 parts)

2021 GMC Sierra 3500 HD(2,276 parts)

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Other GMC Sierra 3500 HD Years

AT4 · Suspension & Steering (78 products)

Cognito 20-24 Chevy/GMC Silverado/Sierra 2500/3500 HD 2WD/4WD Torsion Bar Keys

Cognito 20-24 Chev Silv/Sierra 2500/3500HD SM Series LDG Traction Bar Kit - For 5-9in Rear Lift

Firestone Level Command II Standard Duty Single Analog Air Compressor System Kit (WR17602158)

Tuff Country 20-23 Chevy Silverado GMC Sierra 2500HD/3500HD Ball Joint Upper Control Arms

Firestone Ride-Rite RED Label Air Spring Kit Rear 2020 Chevrolet/GMC 2500/3500 2WD/4WD (W217602709)

SPC Performance 11+ Chevy/GMC 2500HD / 3500HD Upper Camber/Caster Kit

Wehrli 20-24 Chevrolet Duramax Traction Bar Install Kit

Timbren 2011 Chevrolet Silverado 2500 HD Rear Suspension Enhancement System

Air Lift Loadlifter 5000 Ultimate Rear Air Spring Kit for 2020+ Chevrolet Silverado 2500/3500

Fabtech 2in Rear Leaf Spring Block Kit - 3/4in Pin

Timbren 2011 Chevrolet Silverado 2500 HD Rear Suspension Enhancement System

Timbren 2011 Chevrolet Silverado 2500 HD Front Suspension Enhancement System

Body Armor 4x4 2020+ GMC/Chevy 2500HD/3500HD 4WD 1.5in-2in Key and Shock Extender

Fabtech 6in Driver & Passenger Tie Rod Assembly Kit

Hellwig 20-22 Chevrolet Silverado 2500 HD Solid Heat Treated Chromoly 1-5/16in Big Wig Rear Sway Bar

Hellwig 20-22 Chevrolet Silverado 2500/3500 HD 2/4WD Solid Chromoly 1-1/4in Rear Sway Bar

Hellwig 20-21 Chevy Silv 3500 Load Pro- 3500lb Level LC 4 Leaf Stack Helper Spring w/o Mounting Kit

Unity Automotive Front Shock Absorbers - 2-211090-001

Firestone Ride-Rite Air Helper Spring Kit Rear Chevy/GMC HD 2500/3500 (W217602613)

Firestone 11-24 Chevrolet Silverado 2500 2WD/4WD AIO Analog Ride-Rite All-In-One Kit (W217602873)

Frequently Asked Questions

Do these parts fit my 2021 GMC Sierra 3500 HD AT4?

What suspension & steering options are available for my 2021 GMC Sierra 3500 HD AT4?

What brands make parts for the 2021 GMC Sierra 3500 HD AT4?

How fast do 2021 GMC Sierra 3500 HD AT4 parts ship?

What warranty do your 2021 GMC Sierra 3500 HD AT4 parts come with?