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 robust and capable heavy-duty pickup truck aimed at buyers needing substantial towing and payload capacity. The Crew Cab Standard Bed configuration, paired with the 6.6-liter V8 gasoline engine producing 401 horsepower, represents a popular choice for those seeking a balance between power, comfort, and practicality. This particular variant occupies a middle ground in the Sierra 3500HD lineup, offering more power than the base diesel option but remaining more accessible than the higher-output Duramax diesel models.
Technical Specifications
| Brand | GMC |
| Model | Sierra 3500HD |
| Generation | Sierra 3500HD V (GMTT1XX, facelift 2024) Crew Cab Standard Bed |
| Type (Engine) | 6.6 V8 (401 Hp) SRW 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 | 7.7 kg/Hp, 129.4 Hp/tonne |
| Weight-to-torque ratio | 4.9 kg/Nm, 203 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 | 3098 kg (6829.92 lbs) |
| Max. weight | 5080 kg (11199.48 lbs) |
| Max load | 1982 kg (4369.56 lbs) |
| Fuel tank capacity | 136 l (35.93 US gal | 29.92 UK gal) |
| Permitted trailer load with brakes (12%) | 7257 kg (15998.95 lbs) |
| Length | 6369 mm (250.75 in) |
| Width including mirrors | 2079 mm (81.85 in) |
| Height | 2054 mm (80.87 in) |
| Wheelbase | 4037 mm (158.94 in) |
| Front track | 1731 mm (68.15 in) |
| Rear (Back) track | 1736 mm (68.35 in) |
| Ride height (ground clearance) | 284 mm (11.18 in) |
| Drivetrain Architecture | The Internal combustion engine (ICE) drives the rear wheels of the vehicle. |
| Drive wheel | Rear wheel drive |
| 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, 360×34 mm |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Cone worm with recirculation balls |
| Power steering | Hydraulic Steering |
| Tires size | 275/70 R18; 275/65 R20 |
| Wheel rims size | 8J x 18; 8.5J x 20 |
Powertrain & Engine Architecture
At the heart of this Sierra 3500HD variant 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 contributes to improved fuel efficiency and power output compared to traditional port fuel injection. The engine produces 401 horsepower at 5200 rpm and 464 lb-ft of torque at 4000 rpm. The engine’s robust construction is designed for heavy-duty applications, prioritizing durability and longevity. The engine is mated to a 10-speed Allison automatic transmission, a hallmark of GMC’s heavy-duty trucks. This transmission is known for its smooth shifting and ability to handle significant torque loads. The Allison transmission is electronically controlled, optimizing shift points for both performance and fuel economy.
Driving Characteristics
The 6.6L V8 and 10-speed Allison combination delivers a confident driving experience, particularly when towing or hauling heavy loads. While not as quick as some lighter-duty pickups, the Sierra 3500HD provides ample power for merging onto highways and maintaining speed even when fully loaded. The 10-speed transmission helps keep the engine in its optimal power band, providing responsive acceleration. Compared to the diesel options, the gasoline engine is noticeably quieter and smoother, offering a more refined driving experience for daily use. However, it lacks the low-end torque of the diesel engines, which can be advantageous for demanding towing scenarios. The rear-wheel-drive configuration provides a traditional truck feel, and the hydraulic steering offers a connected and responsive experience.
Equipment & Trim Levels
The 2024 Sierra 3500HD Crew Cab Standard Bed with the 6.6L V8 typically comes standard with a comprehensive suite of features. These include a user-friendly infotainment system with a touchscreen display, Apple CarPlay and Android Auto compatibility, and a rearview camera. Interior appointments generally include cloth upholstery, though leather options are available as upgrades. Standard safety features include ABS, stability control, and multiple airbags. Higher trim levels, such as the Denali, add premium features like leather upholstery, heated and ventilated seats, a premium sound system, and advanced driver-assistance systems like adaptive cruise control and lane departure warning.
Chassis & Braking
The Sierra 3500HD features a robust chassis designed to withstand the stresses of heavy-duty use. The front suspension utilizes an independent torsion bar and double wishbone setup, 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. The front brakes measure 355x40mm, while the rear brakes are 360x34mm. An Anti-lock Braking System (ABS) is standard, enhancing safety and control during emergency braking situations.
Market Reception & Comparison
The 2024 GMC Sierra 3500HD with the 6.6L V8 received generally positive reviews. Critics praised its powerful engine, smooth-shifting transmission, and comfortable ride. Compared to the diesel options, the gasoline engine was noted for its quieter operation and lower initial cost. However, fuel economy is a significant drawback compared to the diesel engines, especially when towing. Against competitors like the Ford Super Duty and Ram 3500, the Sierra 3500HD holds its own in terms of capability and features, often being praised for its refined interior and user-friendly technology.
Legacy
The 6.6L gasoline V8 engine has proven to be a reliable and durable powerplant in GMC and Chevrolet heavy-duty trucks. While not as fuel-efficient as the diesel alternatives, it offers a compelling combination of power, affordability, and simplicity. In the used car market, Sierra 3500HD models equipped with this engine are generally well-regarded for their longevity and relatively low maintenance costs. The Allison 10-speed automatic transmission is also known for its durability and smooth operation, contributing to the overall reliability of this powertrain combination. As the heavy-duty truck market continues to evolve, the 6.6L V8 remains a viable option for buyers who prioritize gasoline power and a proven track record.
