The GMC Sierra 1500 V (GMTT1XX) Double Cab 2.7 Turbo, produced from 2018 to 2021, represented a significant entry point into the full-size pickup truck market for General Motors. Positioned as a more accessible option within the Sierra 1500 lineup, this variant offered a blend of capability, technology, and fuel efficiency, appealing to buyers who didn’t require the higher towing capacities or performance of larger engine options. It was a key component of the fourth generation Sierra 1500, sharing its platform with the Chevrolet Silverado 1500.
Technical Specifications
| Brand | GMC |
| Model | Sierra 1500 |
| Generation | Sierra 1500 V (GMTT1XX) Double Cab |
| Type (Engine) | 2.7 Turbo (310 Hp) 4WD Automatic |
| Start of production | 2018 |
| End of production | 2021 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Pick-up |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 12.4 l/100 km (19 US mpg) |
| Fuel consumption (extra urban) | 10.7 l/100 km (22 US mpg) |
| Fuel Type | Petrol (Gasoline) |
| Weight-to-power ratio | 7.2 kg/Hp |
| Weight-to-torque ratio | 4.7 kg/Nm |
| Power | 310 Hp @ 5600 rpm |
| Power per litre | 113.7 Hp/l |
| Torque | 473 Nm @ 1500-4000 rpm (348.87 lb.-ft.) |
| 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 | 2241 kg (4940.56 lbs.) |
| Max. weight | 3175 kg (6999.68 lbs.) |
| Max load | 934 kg (2059.12 lbs.) |
| Fuel tank capacity | 91 l (24.04 US gal | 20.02 UK gal) |
| Permitted trailer load with brakes (12%) | 3039 kg (6699.85 lbs.) |
| Length | 5886 mm (231.73 in.) |
| Width including mirrors | 2063 mm (81.22 in.) |
| Height | 1921 mm (75.63 in.) |
| Wheelbase | 3745 mm (147.44 in.) |
| Drivetrain Architecture | All wheel drive (4×4) |
| 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, 345 mm |
| Rear brakes | Ventilated discs, 360 mm |
| 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
The heart of the Sierra 1500 V 2.7 Turbo was the GM L3B 2.7-liter turbocharged inline-four engine. This engine represented a departure from the traditional V6 and V8 options typically found in full-size trucks. The L3B utilized direct injection and a twin-scroll turbocharger, along with variable valve timing (VVT) and Displacement on Demand (DOD) cylinder deactivation technology. DOD allowed the engine to shut down two cylinders under light load conditions, improving fuel economy. The engine was paired exclusively with an eight-speed automatic transmission (8L45), chosen for its wide gear ratio spread and smooth shifting characteristics. This transmission helped optimize both fuel efficiency and towing performance.
Driving Characteristics
The 2.7-liter turbo engine provided a surprisingly capable driving experience for a full-size pickup. While not as powerful as the larger V8 options, it delivered a respectable 310 horsepower and 473 lb-ft of torque. The turbocharger provided a noticeable boost in power, particularly at lower RPMs, making it suitable for everyday driving and light-duty tasks. The eight-speed automatic transmission was well-tuned, offering smooth and responsive shifts. Compared to the 5.3L V8, the 2.7T offered a more refined and fuel-efficient experience, but lacked the outright acceleration and towing capacity. The gear ratios were optimized for both on-road comfort and off-road capability, providing adequate power for climbing hills and navigating rough terrain.
Equipment & Trim Levels
The Sierra 1500 V 2.7 Turbo was typically offered in SLE, Elevation, and LT trim levels. Standard features generally included air conditioning, a touchscreen infotainment system with Apple CarPlay and Android Auto compatibility, a rearview camera, and basic safety features like ABS and stability control. Higher trim levels added features such as leather upholstery, heated seats, a premium sound system, and advanced safety technologies like lane departure warning and automatic emergency braking. Optional extras included a larger touchscreen display, a sunroof, and various appearance packages.
Chassis & Braking
The Sierra 1500 V 2.7 Turbo utilized a body-on-frame construction, providing a robust and durable platform. The suspension consisted of an independent coil spring setup at the front and a traditional leaf spring setup at the rear. The rear brakes were typically ventilated discs, a step up from the drums found on some lower trims of other Sierra 1500 models. The braking system was equipped with ABS and electronic brake-force distribution. Steering was provided by an electric power-assisted rack-and-pinion system, offering precise and responsive handling.
Market Reception & Comparison
The 2.7-liter turbo engine received mixed reviews from automotive critics. Some praised its fuel efficiency and surprisingly strong performance, while others found it lacking the refinement and power of the V8 options. Fuel economy figures averaged around 19 mpg in the city and 22 mpg on the highway, making it one of the most fuel-efficient full-size pickups available at the time. Compared to the 5.3L V8, the 2.7T offered better fuel economy but less towing capacity. The 2.7T was often seen as a good choice for buyers who prioritized fuel efficiency and everyday usability over maximum towing and hauling capabilities.
Legacy
The L3B 2.7-liter turbo engine proved to be a relatively reliable powertrain, with few widespread issues reported. The eight-speed automatic transmission also demonstrated good durability. In the used car market, the Sierra 1500 V 2.7 Turbo represents a value-oriented option for buyers seeking a capable and fuel-efficient full-size pickup. While it may not offer the same level of prestige or performance as the V8 models, it provides a practical and affordable alternative. The engine’s combination of turbocharging and cylinder deactivation technology paved the way for future advancements in GM’s powertrain offerings, demonstrating a commitment to both performance and efficiency.
