The GMC Sierra 1500 V (GMTT1XX) Regular Cab Long Box, equipped with the 5.3L V8 engine producing 355 horsepower and paired with a 4WD automatic transmission, was a mainstay of GMC’s full-size pickup truck lineup from 2018 to 2021. This configuration represented a popular balance between capability, affordability, and everyday usability within the broader Sierra 1500 range. It catered to buyers needing a robust work truck or a capable hauler without the added expense of higher trim levels or more powerful engine options. The GMTT1XX designation refers to the truck’s platform, representing a significant update to the Sierra 1500 series.
Technical Specifications
| Brand | GMC |
| Model | Sierra 1500 |
| Generation | Sierra 1500 V (GMTT1XX) Regular Cab Long Box |
| Type (Engine) | 5.3 V8 (355 Hp) 4WD Automatic |
| Start of production | 2018 |
| End of production | 2021 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Pick-up |
| Seats | 2 |
| Doors | 2 |
| Fuel consumption (urban) | 15.7 l/100 km (15 US mpg, 18 UK mpg, 6.4 km/l) |
| Fuel consumption (extra urban) | 11.8 l/100 km (19.9 US mpg, 23.9 UK mpg, 8.5 km/l) |
| Fuel Type | Petrol (Gasoline) |
| Weight-to-power ratio | 6 kg/Hp, 165.4 Hp/tonne |
| Weight-to-torque ratio | 4.1 kg/Nm, 241.8 Nm/tonne |
| Power | 355 Hp @ 5600 rpm |
| Power per litre | 66.6 Hp/l |
| Torque | 519 Nm @ 4100 rpm (382.79 lb.-ft. @ 4100 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | L82 |
| Engine displacement | 5328 cm3 (325.13 cu. in.) |
| Number of cylinders | 8 |
| Engine configuration | V-engine |
| Cylinder Bore | 96 mm (3.78 in.) |
| Piston Stroke | 92 mm (3.62 in.) |
| Compression ratio | 11:1 |
| Number of valves per cylinder | 2 |
| Fuel injection system | Direct injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | OHV, VVT DI |
| Coolant Capacity | 12.8 l (13.53 US qt | 11.26 UK qt) |
| Kerb Weight | 2146 kg (4731.12 lbs.) |
| Max. weight | 3130 kg (6900.47 lbs.) |
| Max load | 984 kg (2169.35 lbs.) |
| Fuel tank capacity | 107 l (28.27 US gal | 23.54 UK gal) |
| Permitted trailer load with brakes (12%) | 4400 kg (9700.34 lbs.) |
| Length | 5832 mm (229.61 in.) |
| Width including mirrors | 2063 mm (81.22 in.) |
| Height | 1921 mm (75.63 in.) |
| Wheelbase | 3545 mm (139.57 in.) |
| Drivetrain Architecture | All wheel drive (4×4). ICE drives rear wheels, front wheels engaged via clutch. |
| Number of gears and type of gearbox | 6 gears, automatic transmission |
| Front suspension | Independent coil spring |
| Rear suspension | Rigid axle suspension, Leaf spring |
| Front brakes | Ventilated discs, 330×30 mm |
| Rear brakes | Ventilated discs, 345×20 mm |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Electric Steering |
| Tires size | 255/70 R17; 265/70 R17; 265/65 R18 |
| Wheel rims size | 8.0J x 17; 8.5J x 18 |
Powertrain & Engine Architecture
At the heart of this Sierra 1500 variant lies the 5.3-liter L82 V8 engine. This engine is a member of GM’s Small Block family, known for its durability and relatively simple design. The L82 utilizes direct fuel injection (DFI) and Active Fuel Management (cylinder deactivation) to balance power delivery with fuel efficiency. The DFI system precisely meters fuel directly into the combustion chamber, improving combustion efficiency and reducing emissions. Active Fuel Management allows the engine to operate on four cylinders during light-load conditions, such as highway cruising, further enhancing fuel economy. The engine’s valvetrain employs an overhead valve (OHV) configuration with variable valve timing (VVT) to optimize performance across the engine’s operating range. The engine is longitudinally mounted in the chassis. The 6-speed automatic transmission (likely the 6L80) was chosen for its robustness and ability to handle the engine’s torque output. This transmission features electronically controlled shifting and overdrive for improved fuel economy at highway speeds.
Driving Characteristics
The 5.3L V8 with the 6-speed automatic provided a comfortable and capable driving experience. While not as quick as the available 6.2L V8, the 5.3L offered ample power for everyday driving and towing. The automatic transmission was tuned for smooth shifts and predictable performance. The gear ratios were optimized for both acceleration and fuel efficiency. In real-world conditions, the truck felt responsive enough for merging onto highways and passing other vehicles, but it wasn’t designed for outright performance. The 4WD system provided enhanced traction in inclement weather and off-road conditions. Compared to manual transmission versions, the automatic offered greater convenience, especially in stop-and-go traffic. However, some drivers might have preferred the more direct control offered by a manual gearbox.
Equipment & Trim Levels
The Regular Cab Long Box 5.3L 4WD typically served as a work-oriented trim, often the base or a slightly upgraded version. Standard features generally included air conditioning, a basic infotainment system with a touchscreen display, and cloth upholstery. Power windows and locks were commonly included. Optional extras could include upgraded audio systems, a trailer brake controller, and various convenience packages. The interior was functional and durable, prioritizing practicality over luxury. The long bed provided ample cargo space for hauling materials or equipment.
Chassis & Braking
The Sierra 1500 V utilized a body-on-frame construction, providing a robust and durable platform. The front suspension featured independent coil springs, while the rear suspension employed a traditional leaf spring setup. This configuration was designed to handle heavy loads and provide a comfortable ride. The braking system consisted of ventilated disc brakes on all four wheels, with larger rotors at the rear. An Anti-lock Braking System (ABS) was standard. The steering system utilized a rack-and-pinion setup with electric power steering for improved responsiveness and fuel efficiency.
Market Reception & Comparison
The 5.3L V8/automatic combination was widely regarded as a sensible choice for buyers seeking a capable and reliable full-size pickup. Critics praised the engine’s balance of power and fuel economy. Fuel economy figures were typical for the segment, around 15 mpg city and 20 mpg highway. Compared to the 6.2L V8, the 5.3L offered lower fuel consumption but less overall power. Compared to the available diesel engine, the 5.3L provided a lower initial cost but less torque for heavy towing. Reliability was generally good, with the L82 engine proving to be a durable and long-lasting powerplant.
Legacy
The GMTT1XX Sierra 1500 with the 5.3L V8 and automatic transmission remains a popular choice in the used truck market. The L82 engine is known for its longevity and relatively low maintenance costs. While older examples may require routine maintenance, such as oil changes and fluid flushes, the powertrain is generally considered reliable. These trucks continue to offer a compelling combination of capability, affordability, and durability, making them a practical choice for buyers seeking a dependable full-size pickup.
