The GMC Sierra 1500 AT4 3.0 Duramax Turbo-Diesel, introduced with the GMTT1XX facelift in 2022, represents a significant offering in the full-size pickup truck segment. This variant combines a powerful and efficient diesel engine with a capable four-wheel-drive system and the AT4’s off-road focused features. Positioned as a mid-to-upper trim level, it caters to buyers seeking a blend of work capability, towing capacity, and comfortable daily driving. Production for this specific configuration was limited to the 2022 model year.
Technical Specifications
| Brand | GMC |
| Model | Sierra 1500 |
| Generation | Sierra 1500 V (GMTT1XX, facelift 2022) Crew Cab Standard Box |
| Type (Engine) | AT4 3.0 Duramax TD (277 Hp) 4WD Automatic |
| Start of production | 2022 |
| End of production | 2022 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Pick-up |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 11.2 l/100 km (21 US mpg) |
| Fuel consumption (extra urban) | 10.2 l/100 km (23.1 US mpg) |
| Fuel Type | Diesel |
| Weight-to-power ratio | 9.1 kg/Hp |
| Weight-to-torque ratio | 4.1 kg/Nm |
| Power | 277 Hp @ 3750 rpm |
| Torque | 623 Nm @ 1500 rpm (459.5 lb.-ft. @ 1500 rpm) |
| Maximum engine speed | 5100 rpm |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | LM2 |
| Engine displacement | 3000 cm3 (183.07 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | Inline |
| Cylinder Bore | 84 mm (3.31 in.) |
| Piston Stroke | 90 mm (3.54 in.) |
| Compression ratio | 15:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Diesel Commonrail |
| Engine aspiration | Turbocharger, Intercooler |
| Valvetrain | DOHC |
| Engine oil capacity | 6.6 l (6.97 US qt | 5.81 UK qt) |
| Coolant capacity | 20.7 l (21.87 US qt | 18.21 UK qt) |
| Kerb Weight | 2531 kg (5579.9 lbs.) |
| Max. weight | 3175 kg (6999.68 lbs.) |
| Max load | 644 kg (1419.78 lbs.) |
| Fuel tank capacity | 83.3 l (22.01 US gal | 18.32 UK gal) |
| AdBlue tank capacity | 20.5 l (5.42 US gal | 4.51 UK gal) |
| Permitted trailer load with brakes (12%) | 3992 kg (8800.85 lbs.) |
| Length | 6158 mm (242.44 in.) |
| Width | 2063 mm (81.22 in.) |
| Width including mirrors | 2478 mm (97.56 in.) |
| Height | 1987 mm (78.23 in.) |
| Wheelbase | 3989 mm (157.05 in.) |
| Ride height (ground clearance) | 272 mm (10.71 in.) |
| Approach angle | 25.4° |
| Departure angle | 25.9° |
| Ramp-over (brakeover) angle | 19.5° |
| Drivetrain Architecture | All wheel drive (4×4). ICE drives rear wheels, front wheels engaged via clutch. |
| Number of gears and type of gearbox | 10 gears, automatic transmission |
| Front suspension | Independent coil spring |
| Rear suspension | Rigid axle suspension, Leaf spring |
| Front brakes | Ventilated discs, 330×30 mm |
| Rear brakes | Ventilated discs, 345×20 mm |
| Steering type | Steering rack and pinion |
| Power steering | Electric |
| Tires size | 265/65 R18 |
| Wheel rims size | 8.5J x 18 |
INTRODUCTION
The 2022 GMC Sierra 1500 AT4 with the 3.0L Duramax Turbo-Diesel engine and 10-speed automatic transmission is a full-size pickup truck designed to balance capability with efficiency. It falls within the fourth generation (GMTT1XX) of the Sierra 1500, benefitting from the mid-cycle refresh introduced for the 2022 model year. The AT4 trim specifically targets buyers interested in a more rugged aesthetic and enhanced off-road performance compared to lower trims like the SLE or Elevation. This diesel variant offered a compelling alternative to the gasoline-powered engines available in the Sierra 1500 lineup, providing superior fuel economy and impressive torque for towing and hauling.
Powertrain & Engine Architecture
At the heart of this Sierra 1500 AT4 lies the GM LM2 3.0-liter inline-six cylinder turbo-diesel engine. This engine utilizes a common-rail direct fuel injection system, delivering fuel at extremely high pressures for optimized combustion. The engine features a single variable geometry turbocharger (VGT) and an intercooler to enhance power and efficiency. The valvetrain employs a Double Overhead Camshaft (DOHC) design with four valves per cylinder, contributing to improved breathing and overall performance. The engine is longitudinally mounted in the chassis.
The engine is paired with a 10-speed automatic transmission (specifically the 10L80) known for its smooth shifting and wide gear ratio spread. This transmission allows the engine to operate in its most efficient range more often, further contributing to fuel economy. The transmission is electronically controlled and features driver-selectable modes, including a tow/haul mode optimized for heavy loads.
Driving Characteristics
The 3.0L Duramax in the Sierra 1500 AT4 delivers a distinct driving experience compared to the gasoline-powered options. While not offering the outright acceleration of the larger V8 engines, the diesel provides a substantial 459.5 lb-ft of torque at a low 1500 rpm. This translates to effortless towing and hauling capabilities. The 10-speed automatic transmission is well-tuned, providing smooth and responsive shifts. The gear ratios are optimized for both on-road cruising and off-road crawling. The diesel engine is noticeably quieter than gasoline engines, especially at highway speeds. However, it does exhibit some diesel clatter during cold starts and under heavy acceleration. The AT4 trim’s suspension tuning provides a comfortable ride while maintaining good body control, even when carrying a load.
Equipment & Trim Levels
The AT4 trim level comes standard with a number of features designed to enhance both comfort and capability. Standard interior features include leather-appointed seating, heated front seats, a leather-wrapped steering wheel, and an 8-inch touchscreen infotainment system with Apple CarPlay and Android Auto compatibility. Exterior features include a unique black chrome grille, body-color door handles, and 18-inch wheels with all-terrain tires. Available options for the AT4 trim included a power-adjustable steering column, a premium Bose audio system, a head-up display, and advanced safety features such as adaptive cruise control and lane keep assist.
Chassis & Braking
The Sierra 1500 AT4 utilizes a fully boxed frame for enhanced rigidity and durability. The front suspension features independent coil springs, while the rear suspension employs a traditional leaf spring setup. The AT4 trim benefits from a slightly raised suspension compared to lower trims, providing increased ground clearance. Braking duties are handled by ventilated disc brakes on all four wheels, with larger rotors at the rear (345x20mm) compared to some other Sierra 1500 configurations. The truck is equipped with an Anti-lock Braking System (ABS) and electronic stability control.
Market Reception & Comparison
The 2022 GMC Sierra 1500 AT4 3.0L Duramax Diesel received generally positive reviews from automotive critics. It was praised for its fuel efficiency, strong towing capacity, and comfortable ride. Compared to the gasoline-powered Sierra 1500 models, the diesel offered significantly better fuel economy, particularly for those who frequently tow or haul. However, the diesel engine carried a higher price tag. Compared to other diesel-powered full-size trucks, such as the Ford F-150 Power Stroke and the Ram 1500 EcoDiesel, the Sierra 1500 Duramax offered a competitive combination of power, efficiency, and features.
Legacy
The LM2 3.0L Duramax engine has proven to be a reliable and durable powertrain. While long-term reliability data is still accumulating for the 2022 model year, the engine has a solid track record in other GM vehicles. On the used car market, the 2022 Sierra 1500 AT4 3.0L Duramax Diesel holds its value well due to its desirable combination of features and fuel efficiency. The limited production run for this specific configuration may also contribute to its continued demand among truck enthusiasts and buyers seeking a capable and efficient full-size pickup.
