2024 GMC Sierra 3500HD V (GMTT1XX facelift ) Regular Cab Long Bed 6.6 Duramax TD V8 (470 Hp) 4WD DRW Automatic

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 Regular Cab Long Bed configuration, equipped with the 6.6-liter Duramax Turbo-Diesel V8 engine producing 470 horsepower and paired with a 10-speed Allison automatic transmission and four-wheel drive (DRW – Dual Rear Wheel), is a specialized variant aimed at professionals and those requiring maximum capability. Production of this specific configuration began in 2024, building upon the established reputation of the Sierra HD line for robustness and performance.

Technical Specifications

Introduction

The 2024 GMC Sierra 3500HD Regular Cab Long Bed with the 6.6L Duramax engine and 10-speed Allison transmission represents the pinnacle of GMC’s heavy-duty truck capabilities. This configuration is specifically designed for buyers who prioritize maximum towing and payload capacity, often for commercial or demanding personal use. The GMTT1XX platform, updated with the 2024 facelift, incorporates enhanced technology and styling while retaining the core strength and durability expected of a Sierra HD. This particular variant sits at the top end of the Sierra 3500HD lineup in terms of capability, though it may not offer the same level of luxury features as higher trim levels like the Denali.

Powertrain & Engine Architecture

The heart of this Sierra 3500HD is 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 direct injection fuel system with a common rail design. The turbocharger, coupled with an intercooler, provides increased air density for improved combustion and power. The engine produces 470 horsepower at 2800 rpm and a massive 1322 Nm (975 lb-ft) of torque at 1600 rpm. The 10-speed Allison automatic transmission is specifically calibrated to handle the engine’s substantial torque, providing smooth and efficient power delivery. This transmission features electronically controlled shifts and a wide gear ratio spread for optimal towing performance. The OHV valvetrain contributes to the engine’s durability and low-end torque characteristics.

Driving Characteristics

The 2024 Sierra 3500HD 3500HD with the Duramax and Allison combination delivers a driving experience focused on capability rather than outright speed. While 470 horsepower is substantial, the emphasis is on the engine’s immense torque. This translates to effortless towing, even with heavy loads. The 10-speed Allison transmission allows the engine to remain in its optimal power band, minimizing gear hunting and maximizing efficiency. Compared to gasoline-powered Sierra 3500HD models, the diesel offers significantly more torque at lower RPMs, making it ideal for hauling and towing. Compared to other Duramax configurations, the 10-speed Allison provides smoother shifts and improved fuel economy compared to older 6-speed transmissions. The dual rear wheel configuration enhances stability when towing heavy trailers.

Equipment & Trim Levels

The Regular Cab Long Bed configuration typically represents a more work-oriented trim level. Standard features generally include air conditioning, a basic infotainment system with a touchscreen display, and vinyl upholstery. Higher trim levels, such as SLE or AT4, add features like leather upholstery, heated seats, a premium audio system, and advanced safety technologies. Optional extras for this variant could include a trailer brake controller, a fifth-wheel hitch, and various towing packages. The interior is designed for durability and functionality, prioritizing ease of use and long-term reliability.

Chassis & Braking

The Sierra 3500HD’s chassis is built for heavy-duty use. It features a fully boxed frame constructed from high-strength steel. The front suspension utilizes an independent torsion bar and double wishbone design, while the rear suspension employs a rigid axle with leaf springs. This setup provides a comfortable ride while maintaining excellent load-carrying capacity. Braking is handled by ventilated disc brakes on all four wheels, measuring 355×40 mm. An Anti-lock Braking System (ABS) is standard. The dual rear wheel setup contributes to increased braking stability and improved weight distribution.

Market Reception & Comparison

The 2024 GMC Sierra 3500HD with the Duramax diesel engine has consistently received positive reviews for its towing and hauling capabilities. Critics praise the engine’s power and torque, as well as the smooth operation of the 10-speed Allison transmission. Compared to the gasoline-powered Sierra 3500HD, the diesel offers superior fuel economy when towing heavy loads, although it typically commands a higher purchase price. Compared to competitors like the Ford Super Duty and Ram 3500, the Sierra 3500HD is often lauded for its refined ride quality and user-friendly technology. Reliability has generally been good, although diesel engines can be more expensive to maintain than gasoline engines due to the complexity of the fuel injection system and emissions controls.

Legacy

The L5P Duramax engine has established a strong reputation for durability and longevity. With proper maintenance, these engines can reliably exceed 200,000 miles. The 10-speed Allison transmission has also proven to be a robust and dependable component. On the used car market, Sierra 3500HD models equipped with this powertrain combination hold their value well, particularly those that have been well-maintained and used primarily for towing. The 2024 facelifted model is expected to continue this trend, offering buyers a capable and reliable heavy-duty truck for years to come.