The GMC Sierra 3500HD, in its fifth generation (GMTT1XX), received a significant facelift for the 2024 model year. This iteration continues GMC’s tradition of offering a heavy-duty pickup truck geared towards demanding tasks like towing and hauling. The Crew Cab Long Bed configuration, paired with the 6.6-liter V8 gasoline engine producing 401 horsepower, and a four-wheel drive (4WD) dual rear wheel (DRW) setup with an Allison 10-speed automatic transmission, represents a potent and capable work truck aimed at professionals and those requiring substantial payload and towing capacity. This specific combination positions itself as a step up from the standard work truck trims, offering a balance of power, comfort, and capability.
Technical Specifications
| Brand | GMC |
| Model | Sierra 3500HD |
| Generation | Sierra 3500HD V (GMTT1XX, facelift 2024) Crew Cab Long Bed |
| Type (Engine) | 6.6 V8 (401 Hp) 4WD DRW Automatic |
| Start of production | 2024 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Pick-up |
| Seats | 5 |
| Doors | 4 |
| Fuel Type | Petrol (Gasoline) |
| Weight-to-power ratio | 8.3 kg/Hp, 120.2 Hp/tonne |
| Weight-to-torque ratio | 5.3 kg/Nm, 188.6 Nm/tonne |
| Power | 401 Hp @ 5200 rpm |
| Torque | 629 Nm @ 4000 rpm (463.93 lb.-ft. @ 4000 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | L8T |
| Number of cylinders | 8 |
| Engine configuration | V-engine |
| Cylinder Bore | 103.25 mm (4.06 in) |
| Piston Stroke | 98 mm (3.86 in) |
| Compression ratio | 10.8:1 |
| Number of valves per cylinder | 2 |
| Fuel injection system | Direct injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | OHV |
| Engine oil capacity | 7.6 l (8.03 US qt | 6.69 UK qt) |
| Coolant | 14.6 l (15.43 US qt | 12.85 UK qt) |
| Kerb Weight | 3335 kg (7352.42 lbs) |
| Max. weight | 6350 kg (13999.35 lbs) |
| Max load | 3015 kg (6646.94 lbs) |
| Fuel tank capacity | 136 l (35.93 US gal | 29.92 UK gal) |
| Permitted trailer load with brakes (12%) | 8074 kg (17800.12 lbs) |
| Length | 6776 mm (266.77 in) |
| Width including mirrors | 2457 mm (96.73 in) |
| Height | 2049 mm (80.67 in) |
| Wheelbase | 4369 mm (172.01 in) |
| Front track | 1731 mm (68.15 in) |
| Rear (Back) track | 1905 mm (75 in) |
| Ride height (ground clearance) | 264 mm (10.39 in) |
| Drivetrain Architecture | The Internal combustion engine (ICE) drives the rear wheels permanently, and the front wheels are driven through an electrically or mechanically operated clutch if necessary. |
| Drive wheel | All wheel drive (4×4) |
| 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; 8J x 18 |
Introduction
The 2024 GMC Sierra 3500HD Crew Cab Long Bed with the 6.6L V8 and 4WD DRW represents the pinnacle of GMC’s heavy-duty truck offerings. Built on the GMTT1XX platform, this truck is designed for owners who require substantial towing and hauling capabilities. The facelifted 2024 model incorporates updated styling, enhanced technology, and refinements to the powertrain. The DRW configuration (dual rear wheels) significantly increases stability and payload capacity, making it ideal for commercial applications or owners who frequently tow large trailers. This variant sits above the base trims, offering a more refined interior and additional features while remaining focused on work-oriented performance.
Powertrain & Engine Architecture
At the heart of this Sierra 3500HD lies the 6.6-liter L8T V8 gasoline engine. This engine is a naturally aspirated, overhead valve (OHV) design featuring direct fuel injection. The direct injection system optimizes combustion efficiency and power delivery. The engine produces 401 horsepower at 5200 rpm and 629 lb-ft of torque at 4000 rpm. The engine’s robust construction and large displacement contribute to its ability to handle heavy loads consistently. The Allison 10-speed automatic transmission is a key component, providing smooth and efficient power transfer. This transmission is known for its durability and ability to handle high torque outputs. The transmission’s ten forward gears allow for optimized engine operation across a wide range of speeds and loads, improving both fuel economy and towing performance.
Driving Characteristics
The combination of the 6.6L V8 and the Allison 10-speed automatic delivers a driving experience focused on capability rather than outright speed. While not a sports truck, the Sierra 3500HD provides ample power for accelerating with a load or maintaining highway speeds. The 10-speed transmission keeps the engine in its optimal power band, even when towing. Compared to the available Duramax diesel engine, the gasoline V8 offers a different power delivery profile – more immediate torque at higher RPMs, but less low-end grunt. The DRW configuration enhances stability, particularly when towing, reducing sway and improving overall control. The ride quality, even unladen, is firm due to the heavy-duty suspension, but the long wheelbase and well-tuned dampers mitigate some of the harshness.
Equipment & Trim Levels
The Crew Cab Long Bed configuration provides a spacious interior with seating for five passengers. Standard features typically include a user-friendly infotainment system with a touchscreen display, Apple CarPlay and Android Auto compatibility, and a suite of safety features like automatic emergency braking and lane departure warning. Higher trim levels add features such as leather upholstery, heated and ventilated front seats, a premium sound system, and advanced trailering technologies. Optional extras include a power sunroof, a rear-seat entertainment system, and various appearance packages. The 2024 facelift brought updated interior materials and a more modern dashboard layout.
Chassis & Braking
The Sierra 3500HD utilizes a robust chassis designed to withstand heavy loads. The front suspension features an independent torsion bar setup with double wishbones, providing a comfortable ride and good handling. The rear suspension employs a traditional leaf spring design, optimized for load-carrying capacity. Braking duties are handled by ventilated disc brakes on all four wheels, providing ample stopping power even when heavily loaded. The anti-lock braking system (ABS) enhances safety by preventing wheel lockup during hard braking. The DRW configuration necessitates a wider track width, contributing to increased stability.
Market Reception & Comparison
The 2024 GMC Sierra 3500HD has been well-received by critics for its powerful engine, capable towing capacity, and refined interior. Compared to its competitors, such as the Ford Super Duty and Ram 3500, the Sierra 3500HD offers a compelling combination of features and performance. The gasoline V8 engine provides a lower initial cost compared to the diesel options, but typically results in lower fuel economy. The DRW configuration is favored by those who prioritize payload and towing capacity over fuel efficiency. Reliability reports suggest that the Allison transmission is particularly durable, while the gasoline engine has a generally good track record.
Legacy
The GMTT1XX platform Sierra 3500HD, and specifically the 6.6L V8/Allison 10-speed combination, is expected to be a durable and reliable workhorse for years to come. The Allison transmission, in particular, has a reputation for longevity. On the used car market, these trucks are likely to hold their value due to their capability and durability. Regular maintenance, including oil changes and transmission fluid services, will be crucial for ensuring the long-term health of the powertrain. The 2024 facelifted models are expected to command a premium due to their updated features and styling.
