The GMC Sierra 3500HD, in its fifth generation (GMTT1XX), received a significant facelift for the 2024 model year. This iteration represents GMC’s heavy-duty pickup truck offering, positioned above the Sierra 1500 and designed for demanding tasks like towing and hauling. The 2024 Sierra 3500HD is available in a variety of configurations, including Regular Cab, Double Cab, and Crew Cab, with options for both standard and long beds. This article focuses specifically on the Regular Cab Long Bed configuration equipped with the 6.6-liter Duramax Turbo Diesel V8 engine producing 470 horsepower, paired with an Allison 10-speed automatic transmission and a Dual Rear Wheel (DRW) drivetrain.
Technical Specifications
| Brand | GMC |
| Model | Sierra 3500HD |
| Generation | Sierra 3500HD V (GMTT1XX, facelift 2024) Regular Cab Long Bed |
| Type (Engine) | 6.6 Duramax TD V8 (470 Hp) DRW Automatic |
| Start of production | 2024 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Pick-up |
| Seats | 2 |
| Doors | 2 |
| Fuel Type | Diesel |
| Weight-to-power ratio | 7.1 kg/Hp, 141.6 Hp/tonne |
| Weight-to-torque ratio | 2.5 kg/Nm, 398.3 Nm/tonne |
| Power | 470 Hp @ 2800 rpm |
| Power per litre | 71.2 Hp/l |
| Torque | 1322 Nm @ 1600 rpm (975.06 lb.-ft. @ 1600 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | L5P |
| Engine displacement | 6604 cm3 (403 cu. in.) |
| Number of cylinders | 8 |
| Engine configuration | V-engine |
| Cylinder Bore | 103 mm (4.06 in.) |
| Piston Stroke | 99 mm (3.9 in.) |
| Compression ratio | 16:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Diesel Commonrail |
| Engine aspiration | Turbocharger, Intercooler |
| Valvetrain | OHV |
| Engine oil capacity | 9.5 l (10.04 US qt | 8.36 UK qt) |
| Coolant | 28.5 l (30.12 US qt | 25.08 UK qt) |
| Kerb Weight | 3319 kg (7317.14 lbs.) |
| Max. weight | 6350 kg (13999.35 lbs.) |
| Max load | 3031 kg (6682.21 lbs.) |
| Fuel tank capacity | 106 l (28 US gal | 23.32 UK gal) |
| Permitted trailer load with brakes (12%) | 9072 kg (20000.34 lbs.) |
| Length | 6002 mm (236.3 in.) |
| Width including mirrors | 2457 mm (96.73 in.) |
| Height | 2038 mm (80.24 in.) |
| Wheelbase | 3595 mm (141.54 in.) |
| Front track | 1731 mm (68.15 in.) |
| Rear (Back) track | 1905 mm (75 in.) |
| Ride height (ground clearance) | 266 mm (10.47 in.) |
| Drivetrain Architecture | Rear wheel drive. Internal Combustion engine (ICE) drives the rear wheels. |
| Number of gears and type of gearbox | 10 gears, automatic transmission Allison |
| Front suspension | Independent torsion bar, double wishbone |
| Rear suspension | Rigid axle suspension, Leaf spring |
| Front brakes | Ventilated discs, 355×40 mm |
| Rear brakes | Ventilated discs, 355×40 mm |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Cone worm with recirculation balls |
| Power steering | Hydraulic Steering |
| Tires size | 235/80 R17; 235/80 R18 |
| Wheel rims size | 6.5J x 17 |
INTRODUCTION
The 2024 GMC Sierra 3500HD Regular Cab Long Bed with the 6.6L Duramax diesel and Allison transmission represents a work-focused configuration within the broader Sierra HD lineup. Positioned as a heavy-duty solution for commercial users and those requiring substantial towing and payload capacity, this variant prioritizes capability over luxury. The Regular Cab configuration, combined with the long bed, maximizes cargo space and provides a straightforward, utilitarian interior. The facelifted GMTT1XX generation introduced updated styling, enhanced technology, and refinements to the Duramax engine for improved performance and efficiency.
Powertrain & Engine Architecture
At the heart of this Sierra 3500HD lies the L5P 6.6-liter Duramax turbocharged diesel V8 engine. This engine is a cornerstone of GMC’s heavy-duty offerings, known for its robust construction and impressive torque output. The L5P utilizes a cast iron block, aluminum cylinder heads, and a forged steel crankshaft. The engine employs a high-pressure common rail direct fuel injection system, delivering fuel directly into the cylinders at extremely high pressures for optimized combustion. The valvetrain utilizes an overhead valve (OHV) configuration, favored for its durability and simplicity. A variable geometry turbocharger (VGT) and intercooler work in tandem to maximize power and efficiency across the engine’s operating range. The Allison 10-speed automatic transmission is specifically calibrated to handle the immense torque produced by the Duramax engine. This transmission features electronically controlled shifts and a robust internal design for reliable operation under heavy loads.
Driving Characteristics
The combination of the 470 horsepower and 1322 lb-ft of torque delivered by the Duramax engine and managed by the Allison transmission results in a truck capable of prodigious towing and hauling. While not designed for sporty acceleration, the Sierra 3500HD provides ample power for merging onto highways and maintaining speed even when heavily loaded. The 10-speed automatic transmission helps keep the engine in its optimal power band, providing smooth and efficient shifts. Compared to gasoline-powered Sierra 3500HD models, the diesel offers significantly more low-end torque, making it ideal for towing large trailers or navigating challenging terrain. Compared to earlier Duramax engines, the 2024 L5P benefits from refinements that improve throttle response and reduce noise, vibration, and harshness (NVH). The DRW configuration enhances stability when towing heavy loads, distributing the weight more evenly across the rear axle.
Equipment & Trim Levels
The Regular Cab Long Bed configuration of the Sierra 3500HD typically represents the entry point into the heavy-duty lineup. Standard equipment generally includes air conditioning, a basic infotainment system with a touchscreen display, and vinyl upholstery. However, even base models benefit from the 2024 facelift, which brought improvements to interior materials and design. Optional extras for this trim could include upgraded infotainment systems with larger screens, navigation, Apple CarPlay and Android Auto compatibility, a premium audio system, power windows and locks, and various towing packages. Interior upholstery options beyond vinyl were available, and buyers could add features like heated seats and a leather-wrapped steering wheel.
Chassis & Braking
The Sierra 3500HD utilizes a fully boxed frame constructed from high-strength steel, providing a solid foundation for heavy-duty applications. The front suspension features an independent torsion bar setup with double wishbone components, while the rear suspension employs a traditional leaf spring design. This configuration is optimized for load-carrying capacity and stability. Braking duties are handled by ventilated disc brakes at all four corners, providing ample stopping power even when towing. An Anti-lock Braking System (ABS) is standard. The DRW configuration utilizes larger brakes and a wider track width to further enhance braking performance and stability. Steering is accomplished via a hydraulic power steering system with a cone worm and recirculation balls mechanism.
Market Reception & Comparison
The 2024 GMC Sierra 3500HD, particularly the Duramax diesel variant, generally received positive reviews for its towing capacity, robust powertrain, and improved interior. Critics praised the Allison transmission for its smooth shifting and durability. Compared to the gasoline-powered Sierra 3500HD models, the diesel version offers superior fuel economy when towing heavy loads, although the initial purchase price is higher. Compared to competitors like the Ford Super Duty and Ram Heavy Duty, the Sierra 3500HD often ranked competitively in terms of towing capacity and overall capability. Reliability reports suggest the Duramax engine and Allison transmission are generally very durable, although diesel engines can be more expensive to maintain than gasoline engines due to the complexity of the emissions control systems.
Legacy
The L5P Duramax engine has established a strong reputation for reliability and longevity. Well-maintained examples of the 2024 Sierra 3500HD are expected to hold their value reasonably well, particularly those with the Duramax diesel engine. The combination of a robust powertrain, heavy-duty chassis, and ample towing capacity makes this truck a desirable option for those requiring a capable workhorse. As these trucks enter the used market, they are likely to appeal to buyers seeking a proven and reliable heavy-duty pickup for demanding tasks. The DRW configuration will continue to be sought after by those who regularly tow extremely heavy loads.
