The GMC Sierra 3500HD III, specifically the facelifted version produced from 2011 to 2014, represented GMC’s heavy-duty pickup truck offering within the GMT900 platform generation. This variant, configured with a Regular Cab, Long Box, a 6.0-liter V8 engine producing 360 horsepower, a four-wheel-drive (4WD) drivetrain, and a dual rear wheel (DRW) setup paired with an automatic transmission, was positioned as a work-focused, high-capacity truck aimed at customers needing substantial towing and payload capabilities. It served as a crucial component of GMC’s professional-grade image, competing directly with offerings from Ford and Ram in the North American heavy-duty truck market.
Technical Specifications
| Brand | GMC |
| Model | Sierra 3500HD |
| Generation | Sierra 3500HD III (GMT900, facelift 2011) Regular Cab Long Box |
| Type (Engine) | 6.0 V8 (360 Hp) 4WD DRW Automatic |
| Start of production | 2011 |
| End of production | 2014 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Pick-up |
| Seats | 2 |
| Doors | 2 |
| Fuel Type | Petrol (Gasoline) |
| Weight-to-power ratio | 8.2 kg/Hp, 121.7 Hp/tonne |
| Weight-to-torque ratio | 5.7 kg/Nm, 174 Nm/tonne |
| Power | 360 Hp @ 5400 rpm |
| Power per litre | 60.3 Hp/l |
| Torque | 515 Nm @ 4200 rpm, 379.84 lb.-ft. @ 4200 rpm |
| Maximum engine speed | 6000 rpm |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | Vortec L96 |
| Engine displacement | 5967 cm3, 364.13 cu. in. |
| Number of cylinders | 8 |
| Engine configuration | V-engine |
| Cylinder Bore | 101.6 mm, 4 in. |
| Piston Stroke | 92 mm, 3.62 in. |
| Compression ratio | 9.6:1 |
| Number of valves per cylinder | 2 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | OHV, VVT |
| Engine oil capacity | 5.7 l, 6.02 US qt | 5.02 UK qt |
| Coolant | 15.5 l, 16.38 US qt | 13.64 UK qt |
| Kerb Weight | 2959 kg, 6523.48 lbs. |
| Max. weight | 6078 kg, 13399.7 lbs. |
| Max load | 3119 kg, 6876.22 lbs. |
| Trunk (boot) space – maximum | 2138 l, 75.5 cu. ft. |
| Fuel tank capacity | 136 l, 35.93 US gal | 29.92 UK gal |
| Permitted trailer load with brakes (12%) | 6260 kg, 13800.94 lbs. |
| Length | 5715 mm, 225 in. |
| Width including mirrors | 2436 mm, 95.91 in. |
| Height | 1966 mm, 77.4 in. |
| Wheelbase | 3369 mm, 132.64 in. |
| Front track | 1748 mm, 68.82 in. |
| Rear (Back) track | 1906 mm, 75.04 in. |
| Ride height (ground clearance) | 218 mm, 8.58 in. |
| Minimum turning circle (turning diameter) | 13.9 m, 45.6 ft. |
| Drivetrain Architecture | The Internal combustion engine (ICE) drives the rear wheels permanently, and the front wheels are driven through an electrically or mechanically operated clutch if necessary. |
| Drive wheel | All wheel drive (4×4) |
| Number of gears and type of gearbox | 6 gears, automatic transmission Hydra-Matic |
| 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, 373×34 mm |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Cone worm with recirculation balls |
| Tires size | 235/80 R17; 265/70 R18 |
Powertrain & Engine Architecture
At the heart of this Sierra 3500HD variant lies the Vortec L96 engine, a 6.0-liter (364 cubic inches) V8. This engine is a member of the Vortec family, known for its robust construction and relatively simple design. The L96 features a cast iron block and aluminum cylinder heads, contributing to its durability. It utilizes a multi-port fuel injection system, delivering fuel to each cylinder individually for optimized combustion. The engine employs an overhead valve (OHV) valvetrain with variable valve timing (VVT) on the intake side, enhancing low-end torque and improving fuel efficiency. The 6L90E Hydra-Matic six-speed automatic transmission was the standard pairing for this engine. This transmission is known for its durability and ability to handle the high torque output of the L96, crucial for heavy-duty applications. The 4WD system is a traditional part-time system, allowing the driver to switch between two-wheel drive and four-wheel drive as needed.
Driving Characteristics
The 6.0L V8 with the 6L90E automatic transmission delivers a balance of power and usability. While not as quick as some of the diesel-powered or higher-output gasoline variants, the 360 horsepower and 380 lb-ft of torque provide ample capability for towing and hauling. The automatic transmission offers smooth shifts, although it may not be as responsive as a manual transmission. The gear ratios are optimized for towing, providing strong low-end torque. In real-world conditions, this setup feels capable and confident when loaded, but can feel somewhat sluggish when driving unloaded. Compared to the available Duramax diesel engine, this gasoline variant offers less torque and lower fuel economy, but it is generally less expensive to purchase and maintain.
Equipment & Trim Levels
The Regular Cab, Long Box configuration of the Sierra 3500HD typically came with a fairly basic level of equipment, reflecting its work-truck focus. Standard features included air conditioning, a basic audio system, and vinyl upholstery. Higher trim levels, such as the LT, added features like cloth or leather upholstery, power windows and locks, and upgraded audio systems. Optional extras included a trailer brake controller, a navigation system, and various towing packages. The interior design was functional and durable, prioritizing practicality over luxury.
Chassis & Braking
The Sierra 3500HD’s chassis is built for heavy-duty use. It features a fully boxed frame for increased rigidity and strength. The front suspension utilizes an independent torsion bar setup with double wishbone components, providing a comfortable ride and good handling. The rear suspension employs a traditional leaf spring setup, designed to handle heavy loads. Braking duties are handled by ventilated disc brakes on all four wheels, providing adequate stopping power. An Anti-lock Braking System (ABS) is standard. The DRW configuration (dual rear wheels) significantly increases the truck’s stability and load-carrying capacity.
Market Reception & Comparison
The 2011-2014 GMC Sierra 3500HD with the 6.0L V8 and automatic transmission received generally positive reviews, particularly from those who prioritized gasoline engine simplicity and lower upfront cost. Critics noted that the diesel variants offered superior towing capacity and fuel economy, but the gasoline engine provided a viable option for those who didn’t require the absolute maximum in those areas. Fuel economy was typical for a heavy-duty pickup truck, averaging around 14-16 mpg in combined driving. Reliability was generally good, although some owners reported issues with the fuel injectors and the transmission.
Legacy
The Vortec L96 engine and 6L90E transmission combination proved to be a durable and reliable powertrain. While the diesel variants have become increasingly popular, the gasoline-powered Sierra 3500HD remains a capable and affordable option in the used truck market. These trucks are often sought after by those who need a heavy-duty pickup for work or recreational purposes, but prefer the simplicity and lower maintenance costs of a gasoline engine. The GMT900 platform, as a whole, is considered a robust and well-engineered design, contributing to the long-term value of these vehicles.
