The Chevrolet Silverado 3500 HD IV (T1XX) Regular Cab Long Bed, equipped with the 6.6-liter Duramax Turbo Diesel V8 engine producing 445 horsepower and paired with a 10-speed Allison automatic transmission and four-wheel drive, represents a significant offering in the heavy-duty pickup truck segment. Produced from 2020 to 2023, this configuration catered to buyers needing substantial towing and hauling capabilities, positioning itself as a workhorse within the fourth generation (T1XX) Silverado HD lineup. This particular variant occupied a premium space within the range, offering a balance of power, technology, and practicality for demanding tasks.
Technical Specifications
| Brand | Chevrolet |
| Model | Silverado 3500 HD |
| Generation | Silverado 3500 HD IV (T1XX) Regular Cab Long Bed |
| Type (Engine) | 6.6 Duramax TD V8 (445 Hp) 4WD SRW Automatic |
| Start of production | 2020 |
| End of production | 2023 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Pick-up |
| Seats | 2 |
| Doors | 2 |
| Fuel Type | Diesel |
| Weight-to-power ratio | 7.7 kg/Hp, 130 Hp/tonne |
| Weight-to-torque ratio | 2.8 kg/Nm, 360.6 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 | 29.1 l (30.75 US qt | 25.6 UK qt) |
| Kerb Weight | 3422 kg (7544.22 lbs.) |
| Max. weight | 5352 kg (11799.14 lbs.) |
| Max load | 1930 kg (4254.92 lbs.) |
| Fuel tank capacity | 106 l (28 US gal | 23.32 UK gal) |
| Permitted trailer load with brakes (12%) | 9752 kg (21499.48 lbs.) |
| Length | 5982 mm (235.51 in.) |
| Width including mirrors | 2076 mm (81.73 in.) |
| Height | 2056 mm (80.94 in.) |
| Wheelbase | 3595 mm (141.54 in.) |
| Front track | 1731 mm (68.15 in.) |
| Rear (Back) track | 1736 mm (68.35 in.) |
| Ride height (ground clearance) | 285 mm (11.22 in.) |
| Drivetrain Architecture | All wheel drive (4×4). ICE drives rear wheels, front wheels engaged via clutch. |
| 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 | 235/80 R17; 265/70 R17; 245/75 R17; 275/70 R18 |
| Wheel rims size | 7.5J x 17; 8J x 18 |
Powertrain & Engine Architecture
The heart of this Silverado 3500 HD is the Duramax L5P 6.6-liter turbocharged diesel V8 engine. This engine, a staple of GM’s heavy-duty trucks, utilizes a cast iron block and aluminum cylinder heads. The L5P features a diesel commonrail fuel injection system, delivering highly pressurized fuel directly into the cylinders for efficient combustion. The engine employs an overhead valve (OHV) valvetrain, a design choice prioritizing durability and low-end torque. A single variable geometry turbocharger with an intercooler maximizes both power and efficiency. The 10-speed Allison automatic transmission, a robust unit designed to handle the engine’s substantial torque output, provides smooth and efficient gear changes. This transmission features electronically controlled shifts and multiple driving modes, including tow/haul mode, optimizing performance for heavy loads.
Driving Characteristics
The 445 horsepower and 910 lb-ft of torque delivered by the Duramax engine and 10-speed Allison transmission translate into impressive real-world performance. While not designed for outright speed, this Silverado 3500 HD excels at towing and hauling. The 10-speed transmission keeps the engine within its optimal power band, providing strong acceleration even when heavily loaded. Compared to gasoline-powered Silverado 3500 HD models, the diesel offers significantly more low-end torque, making it easier to start and maintain momentum with heavy trailers. The automatic transmission, while convenient, may not offer the same level of control as a manual transmission, but its smooth operation and optimized shift points contribute to a comfortable driving experience.
Equipment & Trim Levels
The Regular Cab Long Bed configuration typically served as a work-oriented trim, though it could be optioned with a surprising amount of comfort and convenience features. Standard equipment generally included air conditioning, a basic infotainment system with a touchscreen display, and vinyl upholstery. Higher trim levels, such as the LT and High Country, added features like leather upholstery, heated and ventilated seats, a premium sound system, and advanced safety technologies like lane departure warning and automatic emergency braking. Optional extras included a gooseneck hitch, bed liner, and various off-road packages.
Chassis & Braking
The Silverado 3500 HD features a fully boxed frame designed for strength and rigidity. The front suspension utilizes an independent torsion bar setup with double wishbones, 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 even when towing heavy loads. The ABS (Anti-lock Braking System) enhances safety by preventing wheel lockup during hard braking. The steering system utilizes a hydraulic power steering setup, offering a responsive and predictable 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, noting its ability to handle demanding tasks with ease. Compared to the gasoline-powered Silverado 3500 HD models, the diesel variant offered superior fuel economy when towing and a more refined driving experience. However, the diesel engine carried a higher price tag and required more frequent maintenance, including diesel exhaust fluid (DEF) refills and particulate filter maintenance. Compared to competitors like the Ford Super Duty and Ram Heavy Duty, the Silverado 3500 HD offered a competitive combination of features, performance, and value.
Legacy
The Duramax L5P engine has proven to be a remarkably durable and reliable powertrain. Well-maintained examples of the 2020-2023 Silverado 3500 HD with this engine configuration continue to command strong resale values in the used car market. The engine’s robust construction and relatively simple design contribute to its longevity. While the particulate filter and diesel exhaust fluid systems require periodic maintenance, the overall reliability of the L5P engine remains high. This particular variant of the Silverado 3500 HD remains a popular choice for buyers seeking a capable and dependable heavy-duty pickup truck.
