GMC Sierra Heavy Duty Headquarters
Dave Smith Motors: The Northwest leader in Professional Grade performance. Explore our deep inventory of Duramax Diesel and Allison transmission builds.
Shop GMC Sierra HD InventoryGMC Sierra HD: Performance Specifications
Compare capability across the Sierra 2500 HD and 3500 HD lineup. Important: Max ratings vary by configuration and equipment. Some max tow figures are based on gooseneck/5th-wheel setups, while conventional (bumper-pull) towing is lower.
| Sierra HD Model | Engine | Transmission | Max Towing | Max Payload |
|---|---|---|---|---|
| Sierra 2500 HD Diesel | 6.6L Duramax® Diesel | Allison® 10-Speed | Up to 22,390 lbs | Up to 3,979 lbs |
| Sierra 2500 HD Gas | 6.6L Gas V8 | Allison® 10-Speed | Up to 19,080 lbs | Up to 3,563 lbs |
| Sierra 3500 HD (SRW) | 6.6L Duramax® Diesel | Allison® 10-Speed | Up to 28,500 lbs | Up to 7,290 lbs |
| Sierra 3500 HD (DRW) | 6.6L Duramax® Diesel | Allison® 10-Speed | Up to 36,000 lbs | Up to 7,286 lbs |
| Denali Ultimate 3500 | 6.6L Duramax® Diesel | Allison® 10-Speed | Up to 36,000 lbs | Up to 5,883 lbs |
Professional Grade: Sierra HD Trim Levels
From work-ready builds to premium luxury, find the configuration that fits your mission.
Pro
The Workhorse
- 6.6L Gas V8 standard
- GMC infotainment system
- LED headlamps/taillamps
- Hitch guidance available
SLE & SLT
Refined Capability
- Available Duramax Diesel
- Digital driver info center
- Leather-appointed seating (trim dependent)
- Trailering tech options
AT4
Off-Road Specialist
- Off-road suspension package
- Recovery hooks
- AT4 exterior accents
- Duramax Diesel available
Denali
Luxury Standard
- Signature Denali styling
- Premium interior materials
- 20" wheel options (trim dependent)
- Advanced driver assist options
Denali Ultimate
The Apex of Sierra HD
- Premium seating upgrades
- Bose audio (package dependent)
- Unique exterior accents
- Super Cruise™ availability varies
Bobby's Accessories Team: GMC HD Upfitting
Don't just buy a truck — buy a complete solution. Our onsite accessories team can help outfit your Sierra 2500 or 3500 for towing, job sites, and work-ready use before you arrive.
- 5th-wheel and gooseneck hitch installs
- Bed protection and liners
- Work-ready suspension and wheel/tire upgrades
- Commercial setups (inventory dependent)
Tip: mention “Accessories / Upfit” so we route you to the right team faster.
GMC Sierra HD FAQs
What is the MultiPro™ Tailgate?
The MultiPro Tailgate (available on select trims) offers multiple configurations designed to improve bed access, loading, and stepping in and out of the box.
Is the Allison 10-speed better for towing?
The Allison® 10-speed is designed for heavy load management, helping keep the Duramax in an effective torque range with smooth shifting and strong grade performance.
Can I buy a Sierra 3500 HD with a custom flatbed at Dave Smith?
Yes. Our onsite accessories team can help coordinate upfits for chassis cab models, including flatbeds and service bodies, depending on availability and build requirements.
How much can a GMC Sierra 2500 tow?
When properly equipped with the 6.6L Duramax Turbo-Diesel, the Sierra 2500 HD can tow up to 22,390 lbs. Gas models can tow up to 19,080 lbs, depending on configuration and equipment.
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