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2026 GMC Sierra HD Denali OVERVIEW

2026 GMC Sierra HD Denali in Alton

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20" Ultra-Bright machined aluminum wheels with bright chrome inserts*
Denali-exclusive authentic wood, patterned aluminum trim and Forge perforated leather seating surfaces
12-way heated and ventilated power front seats
Automatic Emergency Braking

2026 GMC Sierra HD Denali MODELS

Sierra HD Denali
Sierra HD Denali Ultimate

GMC Sierra HD Denali Dealer in Alton

2026 GMC Sierra HD Denali PERFORMANCE

DURAMAX 6.6L TURBO-DIESEL V8 ENGINE

Sierra Heavy Duty’s available Duramax 6.6L Turbo-Diesel V8 engine features an efficient turbocharger and 10-speed automatic transmission.

6.6L V8 GAS ENGINE

Sierra HD Denali’s standard 6.6L V8 gas engine is paired with a 10-speed automatic transmission to help optimize power, torque and efficiency.

ADAPTIVE CRUISE CONTROL WITH TRAILERING

Adaptive Cruise Control* with trailering* allows the luxury heavy-duty truck’s Adaptive Cruise Control to account for additional drag and increased braking distances when towing a trailer.

2026 GMC Sierra HD Denali APPEARANCE

LED PROJECTOR HEADLAMPS

LED projector headlamps feature GMC signature animated lighting sequences.

20" DENALI ULTIMATE WHEELS

The Sierra HD Denali Ultimate luxury truck features attractive 20" Ultra-Bright machined aluminum wheels with gloss-black inserts.*

DENALI ULTIMATE GRILLE

Denali Ultimate impresses with its signature Vader chrome grille, stylish front fascia and chrome recovery hooks.*

2026 GMC Sierra HD Denali COMFORT

PREMIUM DENALI INTERIOR

The Sierra HD Denali luxury truck’s interior distinguishes itself with exceptional materials.

LUXURIOUS DENALI ULTIMATE MATERIALS

Sierra HD Denali Ultimate’s exclusive Alpine Umber interior features refined craftsmanship.

POWER FRONT SEATS WITH MASSAGING FEATURE

Experience serious comfort in Sierra HD Denali Ultimate’s best-in-class* 16-way power front seats with massaging feature.

12-SPEAKER BOSE SOUND SYSTEM

The technologically advanced available 12-speaker Bose* Premium Series with Centerpoint* surround sound helps create a concert-like listening experience.

2026 GMC Sierra HD Denali SAFETY & WARRANTY

PRO GRADE PROTECTION

Standard on every new GMC - GMC Pro Grade Protection has you truly protected with features and services including:

3-year / 36,000-mile Bumper-to-Bumper Limited Warranty
5-year / 60,000-mile Powertrain Limited Warranty
5-year / 60,000-mile Roadside Assistance & Courtesy Transportation
3-year / 36,000-mile Corrosion Protection
6-year / 100,000-mile Rust-Through Protection
First maintenance visit

2026 GMC Sierra HD Denali Safety Main Img

BLIND ZONE STEERING ASSIST

Blind Zone Steering Assist can provide a brief, firm turn of the steering wheel when a potential collision is detected with a moving vehicle in the lane you’re entering.

REAR CROSS TRAFFIC ALERT

Rear Cross Traffic Alert can warn you of detected left or right cross traffic behind your vehicle when you’re in Reverse.

FORWARD COLLISION ALERT

Forward Collision Alert can warn you if it detects a potential front-end collision with a vehicle you’re following so you can quickly take action. It can also provide a tailgating alert if you’re following a vehicle much too closely.

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$7,500 EV Lease Incentive

0% APR For 36 Months For Well-Qualified Buyers

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2026 GMC Sierra HD Denali OVERVIEW

2026 GMC Sierra HD Denali in Alton

2026 GMC Sierra HD Denali MODELS

Sierra HD Denali

Sierra HD Denali Ultimate

GMC Sierra HD Denali Dealer in Alton

2026 GMC Sierra HD Denali PERFORMANCE

DURAMAX 6.6L TURBO-DIESEL V8 ENGINE

6.6L V8 GAS ENGINE

ADAPTIVE CRUISE CONTROL WITH TRAILERING

2026 GMC Sierra HD Denali APPEARANCE

LED PROJECTOR HEADLAMPS

20" DENALI ULTIMATE WHEELS

DENALI ULTIMATE GRILLE

2026 GMC Sierra HD Denali COMFORT

PREMIUM DENALI INTERIOR

LUXURIOUS DENALI ULTIMATE MATERIALS

POWER FRONT SEATS WITH MASSAGING FEATURE

12-SPEAKER BOSE SOUND SYSTEM

2026 GMC Sierra HD Denali SAFETY & WARRANTY

PRO GRADE PROTECTION

BLIND ZONE STEERING ASSIST

REAR CROSS TRAFFIC ALERT

FORWARD COLLISION ALERT

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Disclaimers