The 2011-2013 GMC Sierra 3500HD Crew Cab, equipped with the 6.6-liter Duramax Turbo Diesel V8 engine and an automatic transmission, stands as a significant iteration in GMC’s heavy-duty truck lineage. Produced as part of the GMT900 platform’s facelift, this variant catered to buyers demanding substantial towing and hauling capabilities alongside a degree of interior comfort. It occupied a premium position within the Sierra 3500HD lineup, offering a powerful diesel option for those exceeding the capabilities of gasoline-powered engines. The “SRW” (Single Rear Wheel) designation differentiated it from dual rear wheel (DRW) models designed for even heavier loads.
Technical Specifications
| Brand | GMC |
| Model | Sierra 3500HD |
| Generation | Sierra 3500HD III (GMT900, facelift 2011) Crew Cab Standard Box |
| Type (Engine) | 6.6 Duramax TD V8 (397 Hp) SRW Automatic |
| Start of production | 2011 |
| End of production | 2013 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Pick-up |
| Seats | 5 |
| Doors | 4 |
| Fuel Type | Diesel |
| Weight-to-power ratio | 8.1 kg/Hp, 124.1 Hp/tonne |
| Weight-to-torque ratio | 3.1 kg/Nm, 324.1 Nm/tonne |
| Power | 397 Hp @ 3000 rpm |
| Power per litre | 60.2 Hp/l |
| Torque | 1037 Nm @ 1600 rpm (764.85 lb.-ft. @ 1600 rpm) |
| Maximum engine speed | 3000 rpm |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | Duramax LML |
| Engine displacement | 6599 cm3 (402.7 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 | 24 l (25.36 US qt | 21.12 UK qt) |
| Kerb Weight | 3200 kg (7054.79 lbs.) |
| Max. weight | 5035 kg (11100.27 lbs.) |
| Max load | 1835 kg (4045.48 lbs.) |
| Trunk (boot) space – maximum | 1718 l (60.67 cu. ft.) |
| Fuel tank capacity | 136 l (35.93 US gal | 29.92 UK gal) |
| Permitted trailer load with brakes (12%) | 5897 kg (13000.66 lbs.) |
| Length | 6101 mm (240.2 in.) |
| Width including mirrors | 2032 mm (80 in.) |
| Height | 1966 mm (77.4 in.) |
| Wheelbase | 3904 mm (153.7 in.) |
| Front track | 1748 mm (68.82 in.) |
| Rear (Back) track | 1709 mm (67.28 in.) |
| Ride height (ground clearance) | 213 mm (8.39 in.) |
| Minimum turning circle (turning diameter) | 15.4 m (50.52 ft.) |
| Drivetrain Architecture | 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, 355×40 mm |
| Rear brakes | Ventilated discs, 373×34 mm |
| Tires size | 235/80 R17; 265/70 R18 |
INTRODUCTION
The 2011-2013 GMC Sierra 3500HD Crew Cab featuring the 6.6L Duramax diesel and automatic transmission was a pivotal offering in GMC’s strategy to directly compete with Ford and Ram in the burgeoning heavy-duty truck segment. The GMT900 platform, refreshed with a facelift in 2011, delivered a more refined interior and updated styling compared to its predecessor. This specific configuration targeted customers who needed the substantial towing and payload capabilities of a 3500HD truck, while also appreciating the convenience and comfort of a crew cab and automatic transmission. The SRW designation signifies a single rear wheel configuration, distinguishing it from dual rear wheel (DRW) models designed for even more demanding loads.
Powertrain & Engine Architecture
The core of this Sierra 3500HD is the Duramax LML 6.6-liter turbocharged diesel V8. This engine, a significant advancement over the earlier LBZ and LMM Duramax engines, incorporated a redesigned combustion chamber, an enhanced fuel injection system, and a more robust cooling system. The LML employed a common-rail direct injection system, delivering fuel at exceptionally high pressures for optimized combustion efficiency and reduced emissions. The engine generated 397 horsepower at 3000 rpm and a substantial 765 lb-ft (1037 Nm) of torque at 1600 rpm. The overhead valve (OHV) valvetrain, while a traditional design, was optimized for durability and strong low-end torque. The Allison 6-speed automatic transmission, specifically calibrated for the Duramax engine, provided smooth and dependable shifting, essential for managing the engine’s considerable torque output. This transmission featured a lock-up torque converter to improve fuel efficiency during highway driving.
Driving Characteristics
The pairing of the Duramax engine and Allison transmission resulted in a truck that felt remarkably capable and refined for its size. While not exhibiting the quick acceleration of some gasoline-powered trucks, the 3500HD delivered impressive low-end torque, making it ideally suited for towing heavy loads. The automatic transmission’s gear ratios were optimized for both hauling and highway cruising. Compared to the available manual transmission options, the automatic offered greater ease of use, particularly in stop-and-go traffic or when navigating challenging terrain. However, some drivers favored the more direct feel and control provided by a manual gearbox. The truck’s considerable weight and heavy-duty suspension meant the ride quality, while improved over previous generations, remained firm, especially when the bed was empty.
Equipment & Trim Levels
The Crew Cab configuration provided a spacious interior with seating for five passengers. Standard features generally included air conditioning, power windows and locks, a tilt steering wheel, and a basic audio system. Higher trim levels, such as SLT and Denali, added features like leather upholstery, heated and cooled front seats, a premium audio system, navigation, and a rear-seat entertainment system. Optional extras included a sunroof, upgraded wheels, and various towing packages. The interior design was functional and durable, prioritizing practicality over luxury, although the 2011 facelift introduced improved materials and a more contemporary aesthetic.
Chassis & Braking
The Sierra 3500HD’s chassis was engineered for heavy-duty applications. It featured a fully boxed frame for increased rigidity and strength. The front suspension utilized an independent torsion bar setup with double wishbones, providing a relatively comfortable ride. The rear suspension employed a traditional leaf spring design, optimized for load-carrying capacity. Braking was handled by ventilated disc brakes on all four wheels, delivering ample stopping power even when towing substantial loads. An Anti-lock Braking System (ABS) was standard. The rear axle ratio varied depending on the specific configuration, influencing both towing capacity and fuel economy.
Market Reception & Comparison
The 2011-2013 GMC Sierra 3500HD with the Duramax diesel and automatic transmission was generally well-received by both critics and consumers. It was lauded for its powerful engine, smooth transmission, and impressive towing capacity. Compared to the gasoline-powered versions of the Sierra 3500HD, the Duramax diesel offered significantly better fuel economy when towing and a much higher payload capacity. However, the diesel engine carried a higher initial cost and potentially increased maintenance expenses. When compared to competitors like the Ford Super Duty and Ram 3500, the Sierra 3500HD presented a compelling combination of power, refinement, and capability.
Legacy
The Duramax LML engine and Allison transmission pairing proved to be exceptionally durable and reliable. These trucks remain highly desirable in the used market, particularly among those requiring a capable and dependable work truck. While earlier Duramax engines experienced some issues with emissions systems, the LML engine addressed many of these concerns. Consistent maintenance, including regular oil changes and fuel filter replacements, is crucial for ensuring the longevity of these powertrains. The 2011-2013 Sierra 3500HD represents a sweet spot within the GMT900 generation, offering a refined and capable heavy-duty truck that continues to provide years of reliable service.
