The Chevrolet Silverado 3500 HD IV (T1XX) Crew Cab Standard Bed, equipped with the 6.6-liter Duramax V8 engine producing 445 horsepower and paired with an Allison 10-speed automatic transmission, represents a significant iteration in Chevrolet’s heavy-duty truck lineage. Produced from 2020 through 2023, this configuration occupied a premium position within the Silverado 3500 HD lineup, targeting buyers requiring substantial towing and hauling capabilities without sacrificing everyday usability. It builds upon the foundation of the T1XX platform, introduced to enhance strength, refinement, and technology integration in Chevrolet’s heavy-duty offerings.
Technical Specifications
| Brand | Chevrolet |
| Model | Silverado 3500 HD |
| Generation | Silverado 3500 HD IV (T1XX) Crew Cab Standard Bed |
| Type (Engine) | 6.6 Duramax V8 (445 Hp) SRW Automatic |
| Start of production | 2020 |
| End of production | 2023 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Pick-up |
| Seats | 5 |
| Doors | 4 |
| Fuel Type | Diesel |
| Weight-to-power ratio | 7.7 kg/Hp, 129.5 Hp/tonne |
| Weight-to-torque ratio | 2.8 kg/Nm, 359 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 | 3437 kg (7577.29 lbs.) |
| Max. weight | 5330 kg (11750.64 lbs.) |
| Max load | 1893 kg (4173.35 lbs.) |
| Trunk (boot) space – maximum | 1970 l (69.57 cu. ft.) |
| Fuel tank capacity | 136 l (35.93 US gal | 29.92 UK gal) |
| Permitted trailer load with brakes (12%) | 9752 kg (21499.48 lbs.) |
| Length | 6349 mm (249.96 in.) |
| Width including mirrors | 2079 mm (81.85 in.) |
| Height | 2054 mm (80.87 in.) |
| Wheelbase | 4037 mm (158.94 in.) |
| Front track | 1731 mm (68.15 in.) |
| Rear (Back) track | 1736 mm (68.35 in.) |
| Ride height (ground clearance) | 284 mm (11.18 in.) |
| Drivetrain Architecture | Rear wheel drive. Internal Combustion engine. |
| 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 |
| Tires size | 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 variant is the Duramax L5P 6.6-liter V8 diesel engine. This engine, a staple in Chevrolet and GMC heavy-duty trucks for years, utilizes a cast iron block and aluminum cylinder heads. It employs a Bosch common-rail fuel injection system, delivering fuel at extremely high pressures for optimized combustion. The L5P features a variable geometry turbocharger (VGT) and an intercooler to maximize power and efficiency. The overhead valve (OHV) valvetrain, while a traditional design, is known for its durability and reliability. The Allison 10-speed automatic transmission is a crucial component, designed to handle the engine’s substantial torque output. This transmission offers smooth shifting and a wide gear ratio spread, optimizing both towing performance and fuel economy.
Driving Characteristics
The combination of the 445 hp Duramax engine and the 10-speed Allison transmission delivers a robust driving experience. While not as overtly quick as gasoline-powered trucks, the Silverado 3500 HD excels in situations demanding substantial torque. The 1234 lb-ft of torque is readily available at low RPMs, making it ideal for towing heavy loads or navigating challenging terrain. The 10-speed transmission keeps the engine in its optimal power band, providing confident acceleration even when heavily loaded. Compared to the 6.0L gasoline V8 option, the Duramax offers significantly more torque and improved fuel economy, especially under load. While a manual transmission was not offered with this engine, the Allison automatic provides precise control and minimizes driver fatigue.
Equipment & Trim Levels
The Silverado 3500 HD IV Crew Cab Standard Bed with the Duramax engine typically came in higher trim levels, such as LTZ or High Country. Standard features included a spacious crew cab with seating for five, a user-friendly infotainment system with Apple CarPlay and Android Auto compatibility, and a suite of safety features like automatic emergency braking and lane departure warning. Higher trims added luxury features such as leather upholstery, heated and ventilated front seats, a premium sound system, and advanced trailering technologies. Optional extras included a power sunroof, a rear-seat entertainment system, and various appearance packages.
Chassis & Braking
The Silverado 3500 HD 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, while the rear suspension employs a traditional leaf spring design. This configuration balances ride comfort with load-carrying capacity. Braking duties are handled by ventilated disc brakes on all four wheels, providing ample stopping power even when towing. The rear brakes are slightly larger than the front, reflecting the increased weight typically carried in the rear. Anti-lock brakes (ABS) are standard, enhancing safety and control.
Market Reception & Comparison
The Silverado 3500 HD with the Duramax engine and Allison transmission consistently received positive reviews from automotive critics. It was praised for its powerful engine, smooth transmission, and comfortable ride. Fuel economy, while not exceptional, was considered competitive for a heavy-duty truck. Compared to the gasoline-powered Silverado 3500 HD, the Duramax variant offered superior towing capacity and better fuel efficiency when hauling heavy loads. It also held its own against competitors like the Ford Super Duty and Ram Heavy Duty, often being lauded for its refined interior and advanced technology features.
Legacy
The Duramax L5P engine paired with the Allison 10-speed transmission has proven to be a reliable and durable powertrain. While diesel engines generally require more maintenance than their gasoline counterparts, the Duramax L5P has a strong reputation for longevity. On the used car market, these Silverado 3500 HD models command a premium price due to their capabilities and proven track record. Properly maintained examples continue to provide years of dependable service, making them a popular choice for those needing a capable and reliable heavy-duty truck.
