Skip to main content

2021 GMC Sierra 3500HD Specs & Features

Starting MSRP

Engine TypeGas
Transmission6-speed shiftable automatic
Drive TypeFour wheel drive
Total Seating5
Basic Warranty3 yr./ 36,000 mi.
Fuel & MPG
Fuel & MPG
Fuel typeRegular unleaded
Range in miles (city/hwy)0/0 mi.
Fuel tank capacity36.0 gal.
Base engine size6.6 L
Base engine typeGas
Horsepower401 hp @ 5,200 rpm
Torque464 lb-ft @ 4,000 rpm
Cam typeOverhead valves (OHV)
Valve timingVariable
Direct injectionyes
Towing & Hauling
Towing & Hauling
Max Towing Capacity20,000 lbs.
Max Payload Capacity4,365 lbs.
Transmission6-speed shiftable automatic
Drive typeFour wheel drive
On demand 4WDyes
Electronic hi-lo gear selectionyes
Automatic locking hubsyes
Rear locking differentialyes
Descent controlyes
Front independent suspensionyes
Stabilizer bar stabilizer baryes
Length250.1 in.
Overall width without mirrors81.9 in.
Height80.9 in.
Wheelbase158.9 in.
Bed length82.2 in.
Turning circle52.7 ft.
Ground clearance11.2 in.
Curb weight6,947 lbs.
Maximum towing capacity20,000 lbs.
Maximum payload4,365 lbs.
Gross weight11,350 lbs.
Country of final assemblyUnited States
Exterior Colors
  • Onyx Black
  • Quicksilver Metallic
  • Carbon Black Metallic
  • Hunter Metallic
  • Ebony Twilight Metallic
  • Pacific Blue Metallic
  • White Frost Tricoat
  • Summit White
  • Cayenne Red Tintcoat
Interior Colors
  • Dark Walnut/Dark Ash Grey, premium leather
  • Jet Black, premium leather
Front Seat Dimensions
Front Seat Dimensions
Front head room43.0 in.
Front leg room44.5 in.
Front shoulder room66.0 in.
Front hip room61.2 in.
Premium leatheryes
Bucket front seatsyes
8-way power driver seatyes
Height adjustable driver seatyes
Driver seat with power adjustable lumbar supportyes
2 memorized driver seat settingsyes
8-way power passenger seatyes
Height adjustable passenger seatyes
Passenger seat with power adjustable lumbar supportyes
Multi-level heating driver seatyes
Multi-level heating passenger seatyes
Ventilated driver seatyes
Ventilated passenger seatyes
Rear Seat Dimensions
Rear Seat Dimensions
Rear head room40.1 in.
Rear leg room43.4 in.
Rear shoulder room65.3 in.
Rear hip room60.2 in.
Split-folding rear seatbackyes
Folding with storage center armrestyes
Multi-level heatingyes
Blind spot and lane departure warnings accident avoidance systemyes
Rear cross traffic alertyes
Pre-collision safety systemyes
Post-collision safety systemyes
Dual front side-mounted airbagsyes
Front and rear head airbagsyes
Passenger airbag occupant sensing deactivationyes
Stability controlyes
Traction controlyes
Child seat anchorsyes
Rear door child safety locksyes
4-wheel ABSyes
Front and rear ventilated disc brakesyes
Tire pressure monitoringyes
Dusk sensing headlampsyes
Auto delay off headlampsyes
LED headlampyes
Daytime running lightsyes
Front fog/driving lightsyes
Turn signal mirrorsyes
2 front headrestsyes
Front height adjustable headrestsyes
2 rear headrestsyes
Rear height adjustable headrestsyes
Rear center 3-point beltyes
Engine immobilizeryes
In-Car Entertainment
In-Car Entertainment
AM/FM stereoyes
Bose premium brand speakersyes
7 total speakersyes
1 subwoofer(s)yes
Android Auto/Apple CarPlayyes
USB connectionyes
Auxiliary audio input and USB with external media controlyes
Memory card slotyes
Satellite radio satellite radioyes
Speed sensitive volume controlyes
Power Feature
Power Feature
4 one-touch power windowsyes
Hands-free entryyes
Reverse tilt dual mirrors provides curb view when vehicle in reverseyes
Heated mirrorsyes
Comfort & Convenience
Comfort & Convenience
Keyless ignitionyes
Tilt and telescopic steering wheelyes
Audio and cruise controls on steering wheelyes
Power steeringyes
Front, side, and rear view camerayes
Front and rear parking sensorsyes
Wireless chargingyes
Cruise controlyes
Universal remote transmitter (for garage door, security system, etc.)yes
Front and rear cupholdersyes
Front and rear door pocketsyes
Front seatback storageyes
Leather steering wheelyes
Heated steering wheelyes
Dual zone front climate controlyes
Rear ventilation ductsyes
Sun sensoryes
Dual illuminating vanity mirrorsyes
Electrochromatic inside rearview mirroryes
Turn signal in mirrorsyes
Trip computeryes
External temperature displayyes
Tires & Wheels
Tires & Wheels
Polished alloy wheelsyes
20 in. wheelsyes
All terrain tiresyes
LT275/65R20 tiresyes
Fullsize non-matching spare tireyes
Underbody mounted spare tireyes
Emergency Serviceyes
Airbag Deployment Notificationyes
Stolen Vehicle Tracking/Assistanceyes
Hands-Free Callingyes
Roadside Assistanceyes
Concierge Serviceyes
Destination guidance (also Turn-by-Turn Navigation)yes
Destination Downloadyes
Basic3 yr./ 36,000 mi.
Drivetrain5 yr./ 60,000 mi.
Rust6 yr./ 100,000 mi.
Roadside assistance5 yr./ 60,000 mi.
Free maintenance1 yr./ unlimited mi.
Mechanical Options
Mechanical Options
Engine Block Heater +$100
Heavy Duty Front Spring/Camper Package +$45
Duramax 6.6L Turbo-Diesel V8 Engine +$9,750
Trailer Tire Pressure Monitor Sensors +$50
220 Amp Alternator +$150
Gooseneck Hitch Package +$295
Trailering Wiring Provisions +$35
Auxiliary Battery +$135
Dual Alternators +$380
Gooseneck/5th Wheel Prep Package +$545
High Idle Switch +$200
Snow Plow Prep/Camper Package +$300
Denali Ultimate Package +$1,770
Denali Black Diamond Edition +$2,990
Technology Package +$1,475
GMC Protection Package +$370
Cargo Convenience Package +$515
Interior Options
Interior Options
Rear Under Seat Storage +$275
All-Weather Floor Liner +$210
Lockable Console Vault +$295
Premium Front Floor Liners +$130
Exterior Options
Exterior Options
GMC MultiPro Tailgate Step Lights +$200
Body Color Wheel Arch Moldings +$685
20" Chrome Aluminum Wheels +$2,995
Bedside Storage Boxes +$1,250
Auxiliary Trailer Camera +$595
20" High Gloss Black Aluminum Wheels w/Machined Finish +$1,995
20" Chrome Aluminum Wheels +$2,995
MultiPro Audio System by Kicker +$815
Front License Plate Kit +$0
Power Glass Sunroof +$995
20" High Gloss Black Painted Wheels +$1,995
Tri-fold Soft Tonneau Cover +$700
Power Retractable Assist Steps +$1,100
Black Front and Rear Molded Splash Guards +$190
Cargo Tie-Down Rings +$105