The Chevrolet Silverado 2500 HD III (K2XX) Double Cab Long Box, equipped with the 6.6-liter Duramax TD V8 engine producing 445 horsepower and paired with an automatic transmission, represents a significant iteration in Chevrolet’s heavy-duty truck lineage. Produced from 2017 to 2019, this variant occupied a premium position within the K2XX Silverado 2500/3500 HD range, targeting buyers needing substantial towing and hauling capacity without sacrificing everyday usability. It built upon the foundation of the K2XX platform, introduced in 2015, which focused on increased strength, improved refinement, and enhanced technology compared to its predecessors.
Technical Specifications
| Brand | Chevrolet |
| Model | Silverado 2500 HD |
| Generation | Silverado 2500 HD III (K2XX) Double 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 | 5 |
| Doors | 4 |
| Fuel Type | Diesel |
| Weight-to-power ratio | 7.3 kg/Hp, 137.6 Hp/tonne |
| Weight-to-torque ratio | 2.6 kg/Nm, 381.6 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 | 3234 kg (7129.75 lbs.) |
| Max. weight | 4536 kg (10000.17 lbs.) |
| Max load | 1302 kg (2870.42 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 | 6321 mm (248.86 in.) |
| Width including mirrors | 2045 mm (80.51 in.) |
| Height | 1978 mm (77.87 in.) |
| Wheelbase | 4017 mm (158.15 in.) |
| Front track | 1748 mm (68.82 in.) |
| Rear (Back) track | 1709 mm (67.28 in.) |
| Minimum turning circle (turning diameter) | 16.2 m (53.15 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 | 245/75 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 2500 HD Double Cab Long Box with the 6.6L Duramax diesel and automatic transmission was a workhorse designed for demanding tasks. Positioned as a step up from the gasoline-powered options, and below the even more capable 3500HD models, it catered to owners who frequently towed large trailers, hauled heavy loads, or required a robust truck for commercial or personal use. The “K2XX” designation refers to the platform code for this generation of Silverado and Sierra HD trucks, representing a significant overhaul in terms of chassis strength and overall refinement. The Double Cab configuration offered a balance between passenger space and bed length, making it a versatile choice for families and workers alike.
Powertrain & Engine Architecture
At the heart of this Silverado variant lies the Duramax L5P 6.6-liter turbocharged diesel V8. This engine is a testament to diesel technology, featuring a cast iron block, aluminum cylinder heads, and a robust rotating assembly designed for longevity. The L5P utilizes a common-rail direct fuel injection system, delivering fuel at extremely high pressures for optimized combustion and efficiency. The turbocharger, coupled with an intercooler, provides increased air density for enhanced power output. The engine’s overhead valve (OHV) valvetrain, while seemingly traditional, is known for its durability and simplicity. The Allison 1000 series six-speed automatic transmission is specifically engineered to handle the immense torque produced by the Duramax engine. This transmission features a lock-up torque converter for improved fuel economy and a heavy-duty cooling system to prevent overheating under strenuous conditions. The transmission’s gear ratios are optimized for both towing and everyday driving, providing a balance between power and efficiency.
Driving Characteristics
The Silverado 2500 HD with the Duramax and automatic transmission delivers a driving experience characterized by substantial power and a composed ride, despite its heavy-duty nature. The 445 horsepower and, more importantly, the 910 lb-ft of torque, provide effortless acceleration, even when heavily loaded. The Allison transmission shifts smoothly and decisively, making it easy to maintain control in various driving situations. Compared to the 6.0L gasoline V8, the Duramax offers significantly more low-end torque, making it ideal for towing. While not as nimble as lighter-duty trucks, the Silverado 2500 HD feels surprisingly manageable on the road. The automatic transmission, while convenient, doesn’t offer the same level of control as a manual transmission, particularly when engine braking on steep descents. However, the Allison transmission’s tow/haul mode provides enhanced engine braking and optimized shift points for safer and more efficient towing.
Equipment & Trim Levels
The Silverado 2500 HD offered a range of trim levels, with the Duramax/automatic combination typically found in LT, LTZ, and High Country trims. Standard features on the LT trim included air conditioning, power windows and locks, a basic infotainment system, and cloth upholstery. The LTZ trim added features such as leather upholstery, heated front seats, a premium audio system, and additional chrome exterior trim. The High Country trim represented the pinnacle of luxury, offering features like ventilated front seats, a navigation system, and unique interior and exterior styling cues. Optional extras included a sunroof, a rear-seat entertainment system, and various towing packages. The Double Cab configuration provided ample space for five passengers, with comfortable seating and a usable rear seat.
Chassis & Braking
The K2XX platform features a fully boxed frame constructed from high-strength steel, providing a solid foundation for the truck’s heavy-duty capabilities. The front suspension utilizes an independent torsion bar setup with double wishbone control arms, offering a comfortable ride and predictable 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. An Anti-lock Braking System (ABS) is standard, enhancing safety and control during emergency braking situations. The steering system utilizes a recirculating ball mechanism, providing a robust and reliable steering feel.
Market Reception & Comparison
The Duramax/Allison combination in the Silverado 2500 HD was widely praised by automotive critics for its exceptional towing capacity, smooth power delivery, and overall refinement. Compared to the gasoline-powered Silverado 2500 HD, the Duramax offered significantly better fuel economy when towing heavy loads. However, the Duramax engine carried a higher price tag and required more frequent maintenance, including diesel exhaust fluid (DEF) refills. Compared to the Ford Super Duty and Ram 2500/3500, the Silverado 2500 HD was often seen as a strong competitor, offering a compelling blend of capability, comfort, and value. The Silverado’s interior design was generally considered to be less luxurious than the Ram’s, but its overall build quality and reliability were highly regarded.
Legacy
The Duramax L5P engine and Allison 1000 transmission have proven to be exceptionally reliable powertrains, capable of exceeding 200,000 miles with proper maintenance. The 2017-2019 Silverado 2500 HD with this powertrain remains a popular choice in the used truck market, commanding a premium price due to its proven durability and capability. These trucks are often sought after by owners who require a dependable and powerful workhorse for demanding tasks. The K2XX platform laid the groundwork for subsequent generations of Silverado and Sierra HD trucks, continuing Chevrolet’s legacy of building robust and capable heavy-duty pickups.
