by AT4, AT4X and AT4X AEV Special Edition. Our most off-road-ready heavy-duty range yet.
By Rob Hill, Global CEO, Autogroup International
A new model year only matters if it moves the game forward. The right hand drive 2026 GMC Sierra 2500 HD does exactly that. We have supplied and converted thousands of heavy-duty American pickups for years in Australia, and this is the most capable Sierra HD lineup we have offered. Engineered in the United States and mirror-imaged by Autogroup International for full ADR compliance, it arrives ready for Australian towing, touring and off-road adventure. Choose your trim and bed length, choose diesel or petrol, choose your colours and interior, and we will build it correctly for Australian roads and tracks.
What is new and why it matters in Australia
Most heavy-duty pickups sold locally arrive in a single mid-luxury spec with limited factory off-road hardware. The 2026 Sierra 2500 HD changes the equation with a clear progression of capability from AT4 to AT4X to AT4X AEV Special Edition, plus meaningful factory choices that actually affect how the truck works on sand, gravel and corrugations. Multimatic DSSV spool-valve dampers, a factory suspension lift, 35 inch tyres on 18 inch wheels, and AEV stamped-steel bumpers with integrated recovery points are engineered to work together. The result is a premium highway ride, then calm, predictable control where the bitumen ends. And its critical to mention that after-market upgrades do impact vehicle warranty.
Powertrains and core capability
- Engines: 6.6 litre Duramax diesel around 470 hp and 1,324 Nm, or a 6.6 litre V8 petrol
- Driveline: heavy-duty 10-speed automatic, 4×4 with a two-speed transfer case
- Towing and payload: up to 4.5 ton when correctly equipped and within Australian limits, with payload that varies by NB1 or NB2 configuration
- Trailering tech: Tow and Haul modes, integrated trailer brake controller and multi-view cameras for confident hitching and reversing
The lineup explained
2026 GMC Sierra 2500 HD – AT4
The all-terrain starting point. The right hand drive AT4 brings an Off-Road suspension package with twin-tube Rancho shocks, protective skid plates, hill descent control and all-terrain tyres tuned for sand, gravel and corrugations while keeping highway refinement intact. It rides on 20 inch wheels, and the cabin feels premium with big-screen tech and Jet Black with Kalahari-accented leather. If you want balanced capability with the best conventional towing and payload of the trio, start here.
2026 GMC Sierra 2500 HD AT4X
AT4X steps capability up for tougher tracks. You gain Multimatic DSSV dampers for precise control, a 1.5 inch factory suspension lift, a driver-selectable electronic rear locker, 18 inch wheels and 35 inch Goodyear Territory MT tyres for a taller sidewall and grip. The cabin lifts again with the Obsidian Rush interior, massaging front seats, premium audio and Head-Up Display. If you plan to push deeper off road, this is the sharper tool.
2026 GMC Sierra 2500 HD AT4X AEV Special Edition
AEV adds purpose-built protection and recovery confidence to the AT4X platform. You get AEV stamped-steel front and rear bumpers with integrated recovery points and a winch-ready front design, plus stamped-steel skid plates that protect vital components such as the steering gear, front differential, transfer case and fuel tank as a complete system. Geometry improves, durability goes up, and distinctive AEV styling cues complete the flagship specification.
Differences at a Glance
| Features | AT4 | AT4X | AT4X AEV |
| Off-road focus | Capable all-terrain package for towing and touring in Australia | More control and clearance for tougher tracks | Flagship system with purpose-built protection and recovery hardware |
| Suspension | Off-Road package with twin-tube Rancho shocks | Multimatic DSSV dampers and 1.5 inch factory lift | Same DSSV dampers and 1.5 inch lift as AT4X |
| Rear differential | Automatic locking rear differential | Driver-selectable electronic rear locker | Driver-selectable electronic rear locker |
| Tyres and wheels | 20 inch wheels with all-terrain tyres | 18 inch wheels with 35 inch Goodyear Territory MT tyres | 18 inch AEV Salta wheels with 35 inch Goodyear Territory MT tyres |
| Underbody protection | Skid plates for key areas | Larger steel transfer-case skid and front aluminium skid | AEV stamped-steel bumpers plus stamped-steel skid plates across vital zones |
| Exterior hardware | AT4 grille and red recovery hooks | Lifted stance on 35s for approach and sidewall | AEV bumpers with integrated recovery points and winch-ready front |
| Interior | Jet Black with Kalahari-accented leather, large displays | Obsidian Rush interior, massaging front seats, Bose 12-speaker audio, Head-Up Display | AT4X cabin with AEV branding on headrests and floor liners |
| Tow and payload | Typically the highest of the three | Slightly lower than AT4 due to added hardware | Typically the lowest due to AEV bumpers and armour |
What it feels like to live with
From the driver’s seat the Sierra 2500 HD is calm and accurate. Visibility is excellent, steering is planted and the cabin stays quiet at a cruise. A 13.4 inch centre touchscreen manages nav, media and camera views, and a 12.3 inch driver display keeps information clear. The MultiPro Tailgate, bed lighting and tie-downs make loading simple. Six exterior colours and the available Obsidian Rush interior let you match the truck to your style.
Why upgrade in 2026
If you are in a well-known heavy-duty pickup sold locally in a single middle of the road trim, you already know the limits: fewer factory hardware options, limited tyre sidewall, and little in the way of integrated protection. The right hand drive GMC Sierra 2500 HD gives you three factory off-road paths, real dampers, real tyres and real armour that are validated together. Order the latest specification. Old stock from 2024 or 2025 will miss 2026 feature updates and will be worth less when you go to sell
Buy correctly in Australia
Autogroup International is 100 percent Australian owned by Peter Hill and me. Many Australians knew us for years as American Vehicle Sales. We now align locally with our global Autogroup International brand to reflect the scale and engineering depth behind every right hand drive build. When you buy a Sierra 2500 HD from us you are buying direct from the manufacturer that designs, engineers and converts the vehicle. That keeps costs sensible and gives you faster access to engineering support and parts. Be cautious of independent brokers or so-called sourcing experts who promise to find a truck and send it somewhere else for conversion. Those paths often lack a proper warranty, may not carry the consumer protections you expect, and do not come with the backing of a global automotive program like ours.
Keep exploring and build yours
- Talk to our Melbourne team about AT4, AT4X and AT4X AEV Special Edition
- See our YouTube tour of our Sri Lankan engineering & manufacturing facility
- Learn about our right hand drive engineering and ADR compliance
- Compare bed lengths standard and long
- Choose your colours and interiors including Obsidian Rush
- Select factory options tyres and wheels, protection, trailering and tech
Place your order for the 2026 GMC Sierra 2500 HD in right hand drive. We will build the right truck for Australian roads and Australian adventures.