The GMC Sierra 1500 V (GMTT1XX) Crew Cab Standard Box, equipped with the 2.7-liter turbocharged engine and an 8-speed automatic transmission, was produced for the 2020 and 2021 model years. This configuration represented a key entry point into the refreshed Sierra 1500 lineup, offering a balance of capability, fuel efficiency, and modern technology. Positioned below the larger V8 options, the 2.7 Turbo aimed to attract buyers seeking a versatile full-size pickup without the higher running costs associated with the more powerful engines. It was a significant offering in the highly competitive North American full-size truck market, where fuel economy and everyday usability are increasingly important factors.
Technical Specifications
| Brand | GMC |
| Model | Sierra 1500 |
| Generation | Sierra 1500 V (GMTT1XX) Crew Cab Standard Box |
| Type (Engine) | 2.7 Turbo (310 Hp) Automatic |
| Start of production | 2020 |
| End of production | 2021 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Pick-up |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 11.8 l/100 km (19.9 US mpg) |
| Fuel consumption (extra urban) | 10.2 l/100 km (23.1 US mpg) |
| Fuel Type | Petrol (Gasoline) |
| Weight-to-power ratio | 7 kg/Hp, 143.3 Hp/tonne |
| Weight-to-torque ratio | 4.6 kg/Nm, 218.7 Nm/tonne |
| Power | 310 Hp @ 5600 rpm |
| Power per litre | 113.7 Hp/l |
| Torque | 473 Nm @ 1500-4000 rpm (348.87 lb.-ft. @ 1500-4000 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | L3B |
| Engine displacement | 2727 cm3 (166.41 cu. in.) |
| Number of cylinders | 4 |
| Engine configuration | Inline |
| Cylinder Bore | 92.25 mm (3.63 in.) |
| Piston Stroke | 102 mm (4.02 in.) |
| Compression ratio | 10:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Direct injection |
| Engine aspiration | Turbocharger, Intercooler |
| Valvetrain | DOHC, VVT DI |
| Engine oil capacity | 5.7 l (6.02 US qt | 5.02 UK qt) |
| Coolant capacity | 11.8 l (12.47 US qt | 10.38 UK qt) |
| Kerb Weight | 2163 kg (4768.6 lbs.) |
| Max. weight | 3129 kg (6898.26 lbs.) |
| Max load | 966 kg (2129.67 lbs.) |
| Fuel tank capacity | 91 l (24.04 US gal | 20.02 UK gal) |
| Permitted trailer load with brakes (12%) | 4173 kg (9199.89 lbs.) |
| Length | 6128 mm (241.26 in.) |
| Width including mirrors | 2063 mm (81.22 in.) |
| Height | 1914 mm (75.35 in.) |
| Wheelbase | 3987 mm (156.97 in.) |
| Drivetrain Architecture | Rear wheel drive |
| Number of gears and type of gearbox | 8 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 |
| Steering type | Steering rack and pinion |
| Power steering | Electric Steering |
| Tires size | 255/70 R17; 265/70 R17 |
| Wheel rims size | 8.0J x 17 |
Powertrain & Engine Architecture
The heart of this Sierra 1500 variant is the GM L3B 2.7-liter turbocharged inline-four engine. This engine utilizes direct injection and a twin-scroll turbocharger to deliver a respectable 310 horsepower and 473 lb-ft of torque. The engine features a cast aluminum block and cylinder head, contributing to weight savings. Variable valve timing (VVT) and direct injection are key technologies employed to optimize both power and fuel efficiency. The L3B also incorporates Active Fuel Management (cylinder deactivation), which shuts down two cylinders under light load conditions to further improve fuel economy. The engine is longitudinally mounted in the chassis. Paired with the engine is an 8-speed automatic transmission (likely the 8L45), chosen for its wide gear ratio spread and smooth shifting characteristics. This transmission is designed to maximize fuel efficiency while providing adequate performance for towing and hauling.
Driving Characteristics
The 2.7-liter turbo engine provides adequate power for most everyday driving situations. While not as effortlessly powerful as the larger V8 options, the turbocharger provides a noticeable boost in acceleration when needed. The 8-speed automatic transmission is well-tuned, offering smooth and timely shifts. The gear ratios are optimized for both highway cruising and low-end torque for towing. Compared to the 5.3L V8, the 2.7T feels less refined and has a more noticeable turbo lag. However, it offers significantly better fuel economy. The rear-wheel-drive configuration provides a traditional truck feel, and the suspension is tuned for a comfortable ride, even when carrying a load.
Equipment & Trim Levels
The 2.7 Turbo engine was typically offered on the SLE, Elevation, and AT4 trim levels of the Sierra 1500. Standard features generally included air conditioning, a touchscreen infotainment system with Apple CarPlay and Android Auto compatibility, and a suite of safety features such as automatic emergency braking. Higher trim levels added features like leather upholstery, heated seats, a premium sound system, and advanced driver-assistance technologies. Optional extras included a larger touchscreen display, a sunroof, and various appearance packages.
Chassis & Braking
The Sierra 1500 V utilizes a body-on-frame construction, providing a robust and durable platform. The front suspension consists of independent coil springs, while the rear suspension employs a traditional leaf spring setup. This configuration is designed to handle heavy loads and provide a comfortable ride. Braking duties are handled by ventilated disc brakes on all four wheels, with larger rotors at the rear. Anti-lock brakes (ABS) are standard. The steering system is a rack-and-pinion setup with electric power steering, providing responsive and precise handling.
Market Reception & Comparison
The 2.7-liter turbo engine was generally well-received by critics as a viable alternative to the traditional V8 engines. It offered a good balance of power, fuel efficiency, and affordability. Fuel economy figures were notably better than those of the 5.3L V8, making it an attractive option for buyers who prioritize fuel savings. However, some reviewers noted that the engine could feel strained when towing heavy loads. Compared to the 5.3L V8, the 2.7T offered a lower price point and better fuel economy, but less overall power and towing capacity. The 2.7T was also often compared to the Ford F-150’s EcoBoost engines, which offered similar levels of performance and efficiency.
Legacy
The L3B 2.7-liter turbo engine has proven to be a relatively reliable powertrain. While some early models experienced minor issues with the turbocharger and fuel system, these were generally addressed through software updates and revised components. In the used car market, Sierra 1500s equipped with the 2.7 Turbo engine represent a good value proposition, offering a capable and efficient full-size pickup at a competitive price. The engine’s combination of power, fuel economy, and reliability has made it a popular choice among truck buyers, and it continues to be a significant part of the GMC Sierra 1500 lineup.

