The Chevrolet Silverado 3500 HD III (K2XX) Regular Cab Long Box, equipped with the 6.6-liter Duramax Turbo Diesel V8 engine producing 445 horsepower and paired with a 4WD SRW Automatic transmission, represents a significant iteration in Chevrolet’s heavy-duty truck lineage. Produced from 2017 to 2019, this configuration occupied a premium position within the Silverado 3500 HD lineup, targeting buyers requiring substantial towing and hauling capabilities without sacrificing everyday drivability. It was part of the third generation of the K2XX platform, known for its increased strength and refinement compared to its predecessors.
Technical Specifications
| Brand | Chevrolet |
| Model | Silverado 3500 HD |
| Generation | Silverado 3500 HD III (K2XX) Regular Cab Long Box |
| Type (Engine) | 6.6 Duramax TD V8 (445 Hp) 4WD SRW 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 | 7.3 kg/Hp, 137.3 Hp/tonne |
| Weight-to-torque ratio | 2.6 kg/Nm, 380.7 Nm/tonne |
| Power | 445 Hp @ 2800 rpm |
| Power per litre | 67.5 Hp/l |
| Torque | 1234 Nm @ 1600 rpm (910.15 lb.-ft. @ 1600 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | Duramax L5P |
| Engine displacement | 6588 cm3 (402.02 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 | 3241 kg (7145.18 lbs.) |
| Max. weight | 5171 kg (11400.1 lbs.) |
| Max load | 1930 kg (4254.92 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 | 1979 mm (77.91 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 | All wheel drive (4×4). ICE drives rear wheels, front wheels engaged via clutch. |
| 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, 355 mm |
| Rear brakes | Ventilated discs, 360 mm |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Cone worm with recirculation balls |
| Tires size | 235/80 R17; 265/70 R18 |
| Wheel rims size | 7.5J x 17; 8J x 18 |
Powertrain & Engine Architecture
The heart of this Silverado 3500 HD variant is the Duramax L5P 6.6-liter turbocharged diesel V8 engine. This engine represents a significant evolution of the Duramax design, incorporating technologies to improve both power and efficiency. It features a cast iron block and aluminum cylinder heads, a robust design intended for heavy-duty applications. The L5P utilizes a diesel commonrail fuel injection system, delivering highly pressurized fuel directly into the cylinders for optimized combustion. The turbocharger, coupled with an intercooler, forces more air into the engine, boosting power output. The overhead valve (OHV) valvetrain, while a traditional design, is known for its durability and simplicity. The Allison 1000 six-speed automatic transmission is specifically engineered to handle the high torque output of the Duramax engine. This transmission features electronically controlled shifts and a lock-up torque converter for improved fuel economy.
Driving Characteristics
The combination of the 445 horsepower Duramax engine and the Allison automatic transmission delivers a unique driving experience. While not as overtly sporty as some gasoline-powered trucks, this Silverado 3500 HD offers substantial low-end torque, making it exceptionally capable for towing and hauling. The Allison transmission is programmed for smooth, deliberate shifts, prioritizing stability and control over rapid acceleration. Compared to the 6.0L gasoline V8 option, the Duramax provides significantly more torque, especially at lower RPMs. The automatic transmission, while convenient, does result in a slight performance deficit compared to the available manual transmission, which allows for more direct control over gear selection. However, the automatic’s ease of use is a major benefit for drivers spending long hours on the road or navigating challenging terrain.
Equipment & Trim Levels
The Silverado 3500 HD in this configuration typically came standard with features geared towards work and utility. This included a heavy-duty suspension, a locking rear differential, and a trailer brake controller. Interior appointments were functional and durable, with vinyl or cloth upholstery being common. Standard features also included air conditioning, power windows and locks, and a basic audio system. Optional extras included leather upholstery, heated seats, a premium audio system, navigation, and various driver-assistance technologies. The Regular Cab configuration focused on maximizing cargo space and utility, making it popular with commercial users and those prioritizing functionality over passenger comfort.
Chassis & Braking
The K2XX platform chassis is designed for strength and rigidity. The front suspension utilizes an independent torsion bar setup with double wishbones, providing a comfortable ride while maintaining stability under heavy loads. The rear suspension employs a traditional leaf spring design, known for its durability and load-carrying capacity. Braking duties are handled by ventilated disc brakes on all four wheels, with larger rotors at the rear (360mm) compared to the front (355mm). An Anti-lock Braking System (ABS) is standard, enhancing safety during emergency braking situations. The steering system utilizes a cone worm with recirculation balls, providing a robust and reliable steering feel.
Market Reception & Comparison
The 6.6-liter Duramax diesel engine consistently received positive reviews for its power, reliability, and fuel efficiency. Critics praised the Silverado 3500 HD’s towing and hauling capabilities, making it a top contender in the heavy-duty truck segment. Compared to the gasoline-powered Silverado 3500 HD models, the Duramax diesel offered significantly better fuel economy, especially when towing. However, the diesel engine carried a higher initial cost. Compared to competitors like the Ford Super Duty and Ram Heavy Duty, the Silverado 3500 HD was often seen as offering a good balance of capability, comfort, and value.
Legacy
The Duramax L5P engine has proven to be exceptionally durable and reliable, with many examples exceeding 200,000 miles with proper maintenance. The Allison transmission is also known for its longevity. In the used car market, Silverado 3500 HD models equipped with this powertrain configuration command a premium price due to their reputation for dependability and capability. These trucks remain popular choices for those needing a robust and reliable workhorse for demanding tasks. Regular maintenance, including oil changes and fuel filter replacements, is crucial for ensuring the long-term health of this powertrain.
