The Chevrolet Suburban 3.0d AWD Automatic, introduced for the 2020 model year, marked a significant addition to the full-size SUV segment. This variant, powered by a 3.0-liter Duramax turbocharged diesel engine, positioned itself within the Suburban lineup as a fuel-efficient alternative to the gasoline-powered options, while retaining the substantial space and towing capacity synonymous with the nameplate. It is part of the twelfth generation of the Suburban (GMTT1XX), which featured a comprehensive redesign and updated technology for the iconic SUV.
Technical Specifications
| Brand | Chevrolet |
| Model | Suburban |
| Generation | Suburban (GMTT1XX) |
| Type (Engine) | 3.0d (277 Hp) AWD Automatic |
| Start of production | 2020 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | SUV |
| Seats | 7 |
| Doors | 5 |
| Fuel consumption (urban) | 11.8 l/100 km (19.9 US mpg) |
| Fuel consumption (extra urban) | 9 l/100 km (26.1 US mpg) |
| Fuel consumption (combined) | 10.7 l/100 km (22 US mpg) |
| Fuel Type | Diesel |
| Power | 277 Hp @ 3750 rpm |
| Torque | 623 Nm @ 1500 rpm (459.5 lb.-ft. @ 1500 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | LM2 |
| Number of cylinders | 6 |
| Engine configuration | Inline |
| Cylinder Bore | 84 mm (3.31 in) |
| Piston Stroke | 90 mm (3.54 in) |
| Number of valves per cylinder | 4 |
| Fuel injection system | Diesel Commonrail |
| Engine aspiration | Turbocharger, Intercooler |
| Valvetrain | DOHC |
| Engine oil capacity | 6.6 l (6.97 US qt | 5.81 UK qt) |
| Coolant | 20.7 l (21.87 US qt | 18.21 UK qt) |
| Trunk (boot) space – minimum | 1164 l (41.11 cu. ft) |
| Trunk (boot) space – maximum | 4097 l (144.68 cu. ft) |
| Length | 5732 mm (225.67 in) |
| Width | 2059 mm (81.06 in) |
| Height | 1923 mm (75.71 in) |
| Wheelbase | 3407 mm (134.13 in) |
| Front track | 1741 mm (68.54 in) |
| Rear track | 1734 mm (68.27 in) |
| Drivetrain | All wheel drive (4×4) |
| Number of gears | 10 |
| Gearbox type | Automatic transmission Hydra-Matic |
| Front suspension | Independent coil spring |
| Rear suspension | Independent multi-link suspension |
| Front brakes | Ventilated discs |
| Rear brakes | Ventilated discs |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Electric Steering |
| Tires size | 265/65 R18; 275/60 R20 |
| Wheel rims size | 18; 20 |
Powertrain & Engine Architecture
The core of the Suburban 3.0d is the LM2 3.0-liter inline-six cylinder diesel engine. This engine employs a common-rail direct fuel injection system, injecting fuel directly into the combustion chamber at extremely high pressure to enhance efficiency and minimize emissions. A variable geometry turbocharger, coupled with an intercooler, further boosts performance and responsiveness. The engine features a double overhead camshaft (DOHC) valvetrain, optimizing airflow for increased power output. Paired with the engine is a standard 10-speed Hydra-Matic automatic transmission, offering a broad range of gear ratios for both efficient cruising and robust acceleration. This transmission is recognized for its smooth shifting characteristics and its ability to maintain the engine within its optimal power band.
Driving Characteristics
The 3.0d engine generates 277 horsepower and 459.5 lb-ft of torque, providing ample power to move the substantial weight of the Suburban. While not delivering the same level of outright acceleration as the gasoline-powered V8 options, the diesel offers a more relaxed and refined driving experience. The 10-speed transmission is meticulously tuned, delivering smooth and timely gear changes. Torque is readily available from low engine speeds, making it particularly well-suited for towing and hauling applications. In comparison to the 5.3L or 6.2L V8 models, the 3.0d prioritizes fuel economy and a more linear power delivery. The all-wheel-drive system enhances traction in a variety of weather conditions.
Equipment & Trim Levels
The 3.0d engine was available across several trim levels of the Suburban, including LS, LT, RST, and Premier. Standard features generally included tri-zone automatic climate control, an 8-inch touchscreen infotainment system with Apple CarPlay and Android Auto compatibility, and a comprehensive suite of safety features such as automatic emergency braking and lane departure warning. Higher trim levels added enhancements like leather upholstery, heated and ventilated front seats, a larger touchscreen display, a premium sound system, and advanced driver-assistance technologies like adaptive cruise control and rear cross-traffic alert. Optional extras included a panoramic sunroof, power-adjustable running boards, and a rear-seat entertainment system.
Chassis & Braking
The GMTT1XX Suburban utilizes a fully independent suspension system, featuring coil springs at the front and a multi-link setup at the rear. This configuration contributes to a comfortable ride quality, even on uneven road surfaces. Ventilated disc brakes are standard on all four wheels, providing substantial stopping power. The electronic stability control system and anti-lock braking system (ABS) work in concert to enhance safety and control. The chassis is engineered to manage the vehicle’s considerable weight and provide a stable platform for towing.
Market Reception & Comparison
The Chevrolet Suburban 3.0d was generally well-received by both automotive critics and consumers. It presented a compelling alternative to the gasoline-powered models, particularly for buyers prioritizing fuel economy and towing capabilities. The diesel engine delivered significantly improved fuel economy compared to the V8 options, making it an attractive choice for long-distance travel. Compared to the 5.3L V8, the 3.0d offered comparable towing capacity with enhanced fuel efficiency. However, the diesel engine carried a higher initial purchase price. Reliability reports have been largely positive, with the Duramax diesel engine demonstrating its durability and dependability.
Legacy
The Chevrolet Suburban 3.0d (GMTT1XX) represents a noteworthy advancement in the evolution of this iconic SUV. It reintroduced diesel power to the Suburban lineup after a prolonged absence, offering a fuel-efficient and capable option for buyers. The LM2 engine has proven to be a reliable and durable powerplant, and the 10-speed automatic transmission provides smooth and efficient operation. In the used car market, these Suburbans are highly sought after by individuals seeking a full-size SUV with excellent fuel economy and towing capacity. As of 2024, well-maintained examples continue to retain their value, underscoring the enduring appeal of the Suburban nameplate and the benefits of the 3.0d powertrain.
