2026 GMC Sierra 1500 AT4 Overview

The GMC Sierra 1500 is a light-duty pickup truck known for its power and capabilities. It is available in several trim levels, including the AT4 and AT4X. These high-performance trucks feature a standard diesel engine, making them extra fuel-efficient. Whether you are a longtime diesel truck enthusiast or want to switch from a gas-powered vehicle to a diesel option, learn about the 2026 GMC Sierra 1500 AT4X and AT4 with Texan GMC Buick. We review standard and available features and packages to help you decide whether to schedule a test drive. Contact our dealership in Humble to schedule an appointment, and let us know if you have any questions!

2026 GMC Sierra 1500 AT4 And AT4X: Feature Highlights

Whether you are driving to a job in New Caney or gearing up for a weekend adventure outside Porter, you’ll enjoy a powerful performance and access to many features in the AT4 or AT4X. Check out some standard and available features for both trims:

GMC Sierra 1500 AT4

Key Standard Features: 

• Duramax® 3.0L Turbo-Diesel engine with 10-speed automatic transmission
• 2-inch factory lift with off-road suspension and Rancho® monotube shocks
• Two-speed Autotrac® transfer case and underbody skid plates
• Unique Jet Black interior with Kalahari accents and heated and ventilated perforated front leather seating surfaces

Key Available Features: 

• 15-inch diagonal multicolor Head-Up Display
• 6.2L V8 engine with 10-speed automatic transmission

GMC Sierra 1500 AT4X

Key Standard Features (Includes AT4 key standard features, plus adds or substitutions):

• Front and rear electronic locking differentials
• Multimatic DSSV dampers
• AEV stamped steel front bumper with front winch capability and stamped boron steel front approach AEV skid plate
• 16-way power heated and ventilated front seats with massage feature

Key Available Features: 

• AT4X AEV Edition
• 6.2L V8 engine with 10-speed automatic transmission

2026 GMC Sierra 1500 AT4 And AT4X Available Packages

If you want to customize your new diesel truck, check out some of our favorite packages. These options are available for the GMC Sierra AT4X and AT4:

Cargo Convenience Package

• Rear under-seat storage
• Console-Mounted Safe

GMC Protection Package

• All-weather floor liner
• Front and rear Black molded splash guards

Max Trailering Package

• Trailering Package
• Increased towing and GCWR
• Automatic locking rear differential
• Handling/Trailering Suspension Package
• Enhanced cooling radiator
• Revised shock tuning
• Heavier-duty rear springs and increased RGAWR
• 9.76-inch rear axle
• Trailer brake controller

Sierra Safety Plus Package

• Rear Cross Traffic Braking
• Rear Pedestrian Alert
• Trailer Camera Provisions
• Trailer Side Blind Zone Alert
• HD Surround Vision
• Front and Rear Park Assist

Preferred Package

• Universal Home Remote
• Rear sliding power window
• Hitch Guidance with Hitch View
• In-vehicle Trailering App
• Adaptive Cruise Control
• Rear wheelhouse liners

Test-Drive The GMC Sierra 1500 AT4 Or AT4X Near Houston

Are you ready to get behind the wheel of one of these Sierra 1500 trim levels? Call (281) 299-0566 or message us online today to make your appointment. We look forward to helping you customize your preferred diesel truck. Our team also invites you to browse our financing and leasing options.