The GMC Sierra 2500HD III, specifically the Crew Cab Standard Box configuration with the 6.0-liter V8 engine producing 360 horsepower and paired with a four-wheel-drive system and automatic transmission, was a prominent offering in the heavy-duty pickup truck segment from 2007 to 2010. This generation (GMT900) represented a significant step forward for GMC in terms of capability, refinement, and interior space, aiming to compete directly with offerings from Ford and Dodge. The 6.0L V8/Automatic combination occupied a sweet spot in the lineup, providing a balance of power and usability for both work and personal use, appealing to buyers who needed substantial towing capacity without the higher cost and fuel consumption of the Duramax diesel option.
Technical Specifications
| Brand | GMC |
| Model | Sierra 2500HD |
| Generation | Sierra 2500HD III (GMT900) Crew Cab Standard Box |
| Type (Engine) | 6.0 V8 (360 Hp) 4WD Automatic |
| Start of production | 2007 |
| End of production | 2010 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Pick-up |
| Seats | 5 |
| Doors | 4 |
| Fuel Type | Petrol (Gasoline) |
| Weight-to-power ratio | 7.5 kg/Hp, 133.2 Hp/tonne |
| Weight-to-torque ratio | 5.2 kg/Nm, 190.5 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 LY6 |
| 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 |
| 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 | 2703 kg (5959.09 lbs.) |
| Max. weight | 4173 kg (9199.89 lbs.) |
| Max load | 1470 kg (3240.8 lbs.) |
| Trunk (boot) space – maximum | 1718 l (60.67 cu. ft.) |
| Permitted trailer load with brakes (12%) | 5579 kg (12299.59 lbs.) |
| Length | 6094 mm (239.92 in.) |
| Width including mirrors | 2032 mm (80 in.) |
| Height | 1958 mm (77.09 in.) |
| Wheelbase | 3886 mm (152.99 in.) |
| Front track | 1744 mm (68.66 in.) |
| Rear (Back) track | 1676 mm (65.98 in.) |
| Ride height (ground clearance) | 243 mm (9.57 in.) |
| Minimum turning circle (turning diameter) | 15.6 m (51.18 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, 325×38 mm |
| Rear brakes | Ventilated discs, 325×30 mm |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Cone worm with recirculation balls |
| Tires size | 245/75 R16; 265/75 R17 |
| Wheel rims size | 6.5J x 16; 7.5J x 17 |
Powertrain & Engine Architecture
The heart of this Sierra 2500HD variant is the Vortec LY6 6.0-liter V8 engine. This engine is a member of the Vortec family, known for its robust construction and relatively simple design. It features a cast iron block and aluminum cylinder heads. The LY6 utilizes a traditional overhead valve (OHV) valvetrain, contributing to its durability and ease of maintenance. Fuel delivery is managed by a multi-port fuel injection system, providing adequate fuel atomization for efficient combustion. The engine produces 360 horsepower at 5400 rpm and 515 Nm (379.84 lb-ft) of torque at 4200 rpm. The transmission is a Hydra-Matic 6-speed automatic, chosen for its ability to handle the engine’s torque output and provide smooth shifting. This transmission was a significant upgrade over the older 4-speed automatics, improving both fuel economy and overall driving experience.
Driving Characteristics
The 6.0L V8/Automatic combination in the Sierra 2500HD offered a noticeable step up in performance compared to the base engine options. While not as quick as the diesel variants, it provided ample power for towing and hauling heavy loads. The automatic transmission, while smooth, wasn’t particularly sporty. Gear ratios were optimized for towing and work-related tasks, meaning acceleration wasn’t its strong suit. However, it provided sufficient power for highway cruising and navigating most terrains. Compared to the manual transmission versions, the automatic offered greater convenience, especially in stop-and-go traffic. The 4WD system provided enhanced traction in inclement weather and off-road conditions, making it a versatile vehicle for a wide range of applications.
Equipment & Trim Levels
The Sierra 2500HD offered a range of trim levels, with the 6.0L V8/Automatic configuration typically found in the SLE and SLT trims. Standard features included air conditioning, power windows and locks, a CD player, and cloth upholstery. The SLT trim added features like leather upholstery, heated seats, a premium sound system, and alloy wheels. Optional extras included a navigation system, a sunroof, and a rear-seat entertainment system. The Crew Cab configuration provided spacious seating for five passengers, making it a comfortable option for families and work crews alike.
Chassis & Braking
The GMT900 platform utilized a fully boxed frame for enhanced rigidity and durability. The front suspension featured an independent torsion bar setup with double wishbone control arms, providing a comfortable ride and good handling. The rear suspension employed a traditional leaf spring setup, designed to handle heavy loads. Braking duties were handled by ventilated disc brakes on all four wheels, with ABS (Anti-lock Braking System) as standard equipment. The rear brakes were slightly smaller in diameter than the front brakes, reflecting the weight distribution of the vehicle. The steering system was a cone worm with recirculation balls, providing a solid and predictable feel.
Market Reception & Comparison
The GMC Sierra 2500HD with the 6.0L V8 and automatic transmission was generally well-received by critics and consumers. It was praised for its strong towing capacity, comfortable ride, and spacious interior. Compared to the Duramax diesel variants, it offered a lower price point and simpler maintenance requirements. However, it lacked the diesel’s superior fuel economy and ultimate towing power. Compared to the Ford Super Duty and Dodge Ram 2500, the Sierra 2500HD was often seen as offering a good balance of features and value. Fuel economy was typical for a heavy-duty pickup truck, averaging around 14-16 mpg in combined driving.
Legacy
The GMT900 Sierra 2500HD, particularly the 6.0L V8/Automatic variant, has proven to be a relatively reliable and durable truck. The Vortec LY6 engine is known for its longevity, and the Hydra-Matic transmission, while not without its potential issues, is generally considered to be robust. In the used car market, these trucks remain popular among buyers who need a capable and affordable heavy-duty pickup. Maintenance is relatively straightforward, and parts are readily available. However, potential buyers should be aware of common issues such as oil leaks and corrosion, particularly in areas with harsh winters. Overall, the 2007-2010 GMC Sierra 2500HD 6.0L V8 remains a solid choice for those seeking a dependable and capable work truck.
