The Chevrolet Silverado 2500HD III (K2XX) Regular Cab Long Box, equipped with the 6.6-liter Duramax Turbo Diesel V8 engine producing 445 horsepower and paired with an Allison automatic transmission, represents a significant iteration in Chevrolet’s heavy-duty truck lineage. Produced from 2017 to 2019, this configuration was aimed squarely at buyers needing substantial towing and hauling capability, particularly in the American market where heavy-duty trucks are a mainstay for both work and recreational purposes. This variant occupied a premium position within the 2500HD lineup, offering a balance of power, refinement, and functionality for demanding tasks.
Technical Specifications
| Brand | Chevrolet |
| Model | Silverado 2500 HD |
| Generation | Silverado 2500 HD III (K2XX) Regular Cab Long Box |
| Type (Engine) | 6.6 Duramax TD V8 (445 Hp) Automatic |
| Start of production | 2017 |
| End of production | 2019 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Pick-up |
| Seats | 2 |
| Doors | 2 |
| Fuel Type | Diesel |
| Weight-to-power ratio | 5.9 kg/Hp, 170.9 Hp/tonne |
| Weight-to-torque ratio | 2.1 kg/Nm, 473.9 Nm/tonne |
| Power | 445 Hp @ 2800 rpm |
| Power per litre | 67.4 Hp/l |
| Torque | 1234 Nm @ 1600 rpm (910.15 lb.-ft. @ 1600 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | Duramax 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 | 29.7 l (31.38 US qt | 26.13 UK qt) |
| Kerb Weight | 2604 kg (5740.84 lbs.) |
| Max. weight | 4218 kg (9299.1 lbs.) |
| Max load | 1614 kg (3558.26 lbs.) |
| Trunk (boot) space – maximum | 2162 l (76.35 cu. ft.) |
| Fuel tank capacity | 136 l (35.93 US gal | 29.92 UK gal) |
| Permitted trailer load with brakes (12%) | 6577 kg (14499.8 lbs.) |
| Length | 5699 mm (224.37 in.) |
| Width including mirrors | 2035 mm (80.12 in.) |
| Height | 1976 mm (77.8 in.) |
| Wheelbase | 3393 mm (133.58 in.) |
| Front track | 1748 mm (68.82 in.) |
| Rear (Back) track | 1709 mm (67.28 in.) |
| Minimum turning circle (turning diameter) | 14 m (45.93 ft.) |
| 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 | 6 gears, automatic transmission Allison |
| Front suspension | Independent torsion bar, double wishbone |
| Rear suspension | Rigid axle suspension, Leaf spring |
| Front brakes | Ventilated discs, 350×40 mm |
| Rear brakes | Ventilated discs, 360×34 mm |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Cone worm with recirculation balls |
| Tires size | 235/80 R17; 265/70 R17; 265/70 R18; 265/60 R20 |
| Wheel rims size | 7.5J x 17; 8J x 18; 8.5J x 20 |
INTRODUCTION
The 2017-2019 Chevrolet Silverado 2500HD III, built on the K2XX platform, represented a significant upgrade over its predecessors. This generation focused on increased strength, improved refinement, and enhanced technology. The Regular Cab Long Box configuration, paired with the 6.6L Duramax diesel and Allison automatic, was designed for customers who prioritized capability and durability over passenger space or luxury. It served as a workhorse for commercial applications, agricultural needs, and heavy-duty towing for recreational vehicles and boats. This particular trim level was positioned as a premium offering within the 2500HD range, appealing to those who required substantial power and torque without necessarily opting for the higher trim levels like the High Country.
Powertrain & Engine Architecture
The heart of this Silverado 2500HD is the Duramax L5P 6.6-liter turbocharged diesel V8. This engine is a testament to modern diesel technology, featuring a cast iron block, aluminum cylinder heads, and a robust rotating assembly. The L5P utilizes a diesel commonrail fuel injection system, delivering highly pressurized fuel directly into the cylinders for efficient combustion. The turbocharger, coupled with an intercooler, provides increased air density for enhanced power output. The engine produces 445 horsepower at 2800 rpm and a massive 910 lb-ft (1234 Nm) of torque at 1600 rpm. The Allison 1000 series six-speed automatic transmission is specifically designed to handle the immense torque output of the Duramax engine. This transmission is known for its durability and smooth shifting characteristics, utilizing electronically controlled shifts for optimal performance. The transmission’s gear ratios are optimized for both towing and everyday driving, providing a balance of power and fuel efficiency.
Driving Characteristics
The Silverado 2500HD with the Duramax/Allison combination delivers a driving experience focused on capability and control. While not a sports truck, the abundant torque allows for effortless acceleration, even when heavily loaded. The Allison transmission provides smooth and precise shifts, minimizing gear hunting and maximizing power delivery. Compared to gasoline-powered Silverado 2500HD models, the diesel offers significantly more low-end torque, making it ideal for towing and hauling. Compared to the 6.0L gasoline V8, the Duramax provides a much flatter torque curve, meaning consistent pulling power across a wider range of engine speeds. The ride quality, while firm due to the heavy-duty suspension, is surprisingly comfortable, especially when unladen. The steering is precise, but requires a bit more effort than lighter-duty trucks.
Equipment & Trim Levels
The Regular Cab Long Box 2500HD with the Duramax engine typically came standard with features like air conditioning, power windows and locks, a basic infotainment system with a touchscreen display, and a rearview camera. Interior upholstery was typically vinyl or cloth, reflecting the truck’s work-oriented nature. Optional extras included leather upholstery, heated and ventilated front seats, a premium audio system, navigation, and advanced safety features like lane departure warning and forward collision alert. The Long Box configuration provided ample cargo space for hauling materials or equipment. The standard cab configuration prioritized functionality over passenger comfort, making it ideal for single drivers or those who primarily used the truck for work.
Chassis & Braking
The Silverado 2500HD features a fully boxed frame constructed from high-strength steel, providing a solid foundation for heavy-duty use. The front suspension utilizes an independent torsion bar setup with double wishbones, offering a comfortable ride and precise 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 towing heavy loads. An Anti-lock Braking System (ABS) is standard. The rear axle ratios varied depending on the specific configuration, influencing both towing capacity and fuel economy.
Market Reception & Comparison
The Duramax/Allison combination in the Silverado 2500HD was widely praised by automotive critics for its exceptional towing and hauling capabilities. It consistently outperformed gasoline-powered competitors in these areas. Fuel economy, while not a primary concern for heavy-duty truck buyers, was respectable for a vehicle of this size and capability. Compared to the 6.0L gasoline V8, the Duramax offered significantly better fuel economy when towing heavy loads. Reliability was generally 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. The Silverado 2500HD competed directly with the Ford Super Duty and Ram 2500/3500, each offering similar capabilities and features.
Legacy
The Duramax L5P engine and Allison transmission pairing has proven to be exceptionally durable and reliable. These trucks continue to hold their value in the used car market, particularly those that have been well-maintained. The L5P Duramax is known for its longevity and ability to withstand high mileage. While modern diesel engines are facing increasing scrutiny regarding emissions, the 2017-2019 Silverado 2500HD remains a popular choice for those seeking a capable and dependable heavy-duty truck. The combination of power, durability, and towing capacity ensures its continued relevance in the used truck market for years to come.
