The GMC Sierra 1500 III, produced from 2007 to 2013, represented a significant evolution in GMC’s full-size pickup truck offerings. This generation, designated GMT900, aimed to blend robust capability with improved refinement. Within the Sierra 1500 lineup, the Extended Cab Long Box configuration with the 4.8-liter Vortec V8 engine and four-speed automatic transmission occupied a crucial middle ground, offering a balance between affordability, practicality, and towing capacity. It served as a popular choice for buyers needing more space than a regular cab but not requiring the full size of a crew cab.
Technical Specifications
| Brand | GMC |
| Model | Sierra 1500 |
| Generation | Sierra 1500 III (GMT900) Extended Cab Long Box |
| Type (Engine) | 4.8 Vortec V8 (295 Hp) Automatic |
| Start of production | 2007 |
| End of production | 2013 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Pick-up |
| Seats | 6 |
| Doors | 2 |
| Fuel consumption (urban) | 16.8 l/100 km (14 US mpg) |
| Fuel consumption (extra urban) | 12.4 l/100 km (19 US mpg) |
| Fuel Type | Petrol (Gasoline) |
| Power | 295 Hp @ 5600 rpm |
| Torque | 414 Nm @ 4600 rpm (305.35 lb.-ft. @ 4600 rpm) |
| Maximum engine speed | 6000 rpm |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | LY2 |
| Engine displacement | 4807 cm3 (293.34 cu. in.) |
| Number of cylinders | 8 |
| Engine configuration | V-engine |
| Cylinder Bore | 96.01 mm (3.78 in.) |
| Piston Stroke | 83.06 mm (3.27 in.) |
| Compression ratio | 9.1:1 |
| 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 capacity | 12.7 l (13.42 US qt | 11.17 UK qt) |
| Max. weight | 3130 kg (6900.47 lbs.) |
| Trunk (boot) space – maximum | 2138 l (75.5 cu. ft.) |
| Fuel tank capacity | 128 l (33.81 US gal | 28.16 UK gal) |
| Length | 6325 mm (249.02 in.) |
| Width including mirrors | 2029 mm (79.88 in.) |
| Height | 1870 mm (73.62 in.) |
| Wheelbase | 4001 mm (157.52 in.) |
| Front track | 1730 mm (68.11 in.) |
| Rear track | 1702 mm (67.01 in.) |
| Ride height (ground clearance) | 230 mm (9.06 in.) |
| Minimum turning circle | 15.6 m (51.18 ft.) |
| Approach angle | 16.2° |
| Departure angle | 22.8° |
| Ramp-over angle | 18° |
| Drivetrain Architecture | Rear wheel drive |
| Number of gears and type of gearbox | 6 gears, automatic transmission Hydra-Matic |
| Front suspension | Independent coil spring |
| Rear suspension | Rigid axle suspension, Leaf spring |
| Front brakes | Disc, 330×30 mm |
| Rear brakes | Drum, 295×60 mm |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Electric Steering |
| Tires size | 245/70 R17 |
| Wheel rims size | 7.5J x 17 |
INTRODUCTION
The 2007-2013 GMC Sierra 1500 Extended Cab Long Box, powered by the 4.8L Vortec V8 and paired with a four-speed automatic transmission, was a mainstay of GMC’s truck lineup. Positioned as a mid-range offering, it slotted below the more powerful 5.3L and 6.2L V8 options, and above any potential four-cylinder base models (which were not commonly offered in the US market). This configuration appealed to buyers who prioritized fuel efficiency and affordability without sacrificing significant towing and hauling capabilities. The Extended Cab provided additional passenger space compared to the regular cab, while the Long Box offered a substantial cargo bed for practical use.
Powertrain & Engine Architecture
The heart of this Sierra 1500 variant is the 4.8-liter (293 cubic inch) Vortec V8 engine, designated LY2. This engine is a member of GM’s Vortec family, known for its robust construction and relatively simple design. It features a cast iron block and aluminum cylinder heads, utilizing a 9.1:1 compression ratio. Fuel delivery is managed by a multi-port fuel injection system, providing precise fuel metering for optimal combustion. The overhead valve (OHV) valvetrain, while traditional, proved reliable and contributed to the engine’s longevity. The four-speed Hydra-Matic 4L60-E automatic transmission was the standard pairing. This transmission, while not the most technologically advanced by modern standards, was known for its durability and smooth shifting characteristics. Gear ratios were optimized for a balance of acceleration and fuel economy, with a focus on providing adequate torque for towing and hauling.
Driving Characteristics
The 4.8L V8 and four-speed automatic combination delivered a respectable, though not exhilarating, driving experience. With 295 horsepower and 305 lb-ft of torque, acceleration was adequate for everyday driving and moderate towing. Compared to the 5.3L V8, the 4.8L felt noticeably less powerful, particularly when fully loaded or climbing steep grades. The four-speed automatic, while reliable, lacked the refinement and efficiency of newer transmissions with more gears. The gear ratios were spaced to prioritize low-end torque, making it suitable for work applications, but resulted in higher engine speeds at highway cruising speeds. The rear-wheel-drive configuration provided a traditional truck feel, with predictable handling and good traction in dry conditions.
Equipment & Trim Levels
The Sierra 1500 Extended Cab Long Box 4.8L typically came standard with features like air conditioning, power windows and locks, and an AM/FM stereo. Trim levels varied, with SLE and SLT being the most common. The SLE trim added features such as upgraded cloth upholstery, keyless entry, and a better audio system. The SLT trim offered even more luxury, including leather upholstery, heated seats, and a premium sound system. Optional extras included a navigation system, a sunroof, and various towing packages. Interior materials were generally durable and practical, reflecting the truck’s work-oriented nature. The dashboard layout was functional and straightforward, with easy-to-read gauges and intuitive controls.
Chassis & Braking
The GMT900 Sierra 1500 utilized a body-on-frame construction, providing a robust and durable platform. The front suspension featured independent coil springs, offering a comfortable ride and good handling. The rear suspension employed a traditional leaf spring setup, designed to handle heavy loads. Brakes were disc brakes in the front and drum brakes in the rear, with ABS (Anti-lock Braking System) as standard equipment. The braking system was adequate for the truck’s weight and performance, but lacked the stopping power of more modern braking systems. Steering was rack-and-pinion with power assist, providing responsive and precise steering control.
Market Reception & Comparison
Critics generally viewed the 4.8L Sierra 1500 as a solid, dependable work truck. While it didn’t offer the performance of its larger-engined siblings, it provided a good balance of capability and affordability. Fuel economy was a strong point, particularly compared to the 5.3L and 6.2L models. However, some reviewers noted the four-speed automatic transmission felt dated and limited the truck’s overall efficiency. Compared to competitors like the Ford F-150 and Ram 1500, the Sierra 1500 offered a similar level of capability and features, with GMC’s reputation for build quality and reliability being a key selling point.
Legacy
The 4.8L Vortec V8 and 4L60-E transmission pairing proved to be remarkably durable and reliable. Many examples of these trucks are still on the road today, often with high mileage. While maintenance costs can increase with age, parts availability remains good, and the engine is relatively easy to repair. In the used car market, these Sierra 1500s are often sought after by buyers looking for a dependable and affordable pickup truck. They represent a sweet spot in terms of value and practicality, offering a good combination of capability, comfort, and longevity. The LY2 engine, while not a powerhouse, has earned a reputation as a workhorse, capable of providing years of reliable service with proper maintenance.
