The BMW 3 Series Sedan (E90 LCI), specifically the 320d variant equipped with the Steptronic automatic transmission, represents a significant iteration of BMW’s iconic sports sedan. Introduced with the Life Cycle Impulse (LCI) facelift in 2008 for the 2009 model year and continuing through 2010, this version aimed to refine the E90’s aesthetics and enhance its efficiency. The 320d Steptronic occupied a crucial position in the 3 Series lineup, serving as a fuel-efficient and accessible entry point into the BMW ownership experience, particularly in European markets where diesel engines were highly favored. This configuration balanced performance with practicality, appealing to drivers seeking a premium sedan with lower running costs.
Technical Specifications
| Brand | BMW |
| Model | 3 Series |
| Generation | 3 Series Sedan (E90 LCI, facelift 2008) |
| Type (Engine) | 320d (184 Hp) Steptronic |
| Start of production | 2010 |
| End of production | 2010 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 6.8 l/100 km (34.6 US mpg, 41.5 UK mpg, 14.7 km/l) |
| Fuel consumption (extra urban) | 4.4 l/100 km (53.5 US mpg, 64.2 UK mpg, 22.7 km/l) |
| Fuel consumption (combined) | 5.3 l/100 km (44.4 US mpg, 53.3 UK mpg, 18.9 km/l) |
| CO2 emissions | 140 g/km |
| Fuel Type | Diesel |
| Acceleration 0 – 100 km/h | 7.6 sec |
| Acceleration 0 – 62 mph | 7.6 sec |
| Acceleration 0 – 60 mph | 7.2 sec |
| Maximum speed | 233 km/h (144.78 mph) |
| Emission standard | Euro 5 |
| Weight-to-power ratio | 7.8 kg/Hp, 128.7 Hp/tonne |
| Weight-to-torque ratio | 3.8 kg/Nm, 265.7 Nm/tonne |
| Power | 184 Hp @ 4000 rpm |
| Torque | 380 Nm @ 1900-2750 rpm (280.27 lb.-ft. @ 1900-2750 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | N47D20C |
| Engine displacement | 1995 cm3 (121.74 cu. in.) |
| Number of cylinders | 4 |
| Engine configuration | Inline |
| Cylinder Bore | 84 mm (3.31 in.) |
| Piston Stroke | 90 mm (3.54 in.) |
| Compression ratio | 16.5:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Diesel Commonrail |
| Engine aspiration | Turbocharger, Intercooler |
| Engine oil capacity | 5.2 l (5.49 US qt | 4.58 UK qt) |
| Coolant | 7.9 l (8.35 US qt | 6.95 UK qt) |
| Kerb Weight | 1430 kg (3152.61 lbs.) |
| Max. weight | 1950 kg (4299.01 lbs.) |
| Max load | 520 kg (1146.4 lbs.) |
| Trunk (boot) space – minimum | 460 l (16.24 cu. ft.) |
| Fuel tank capacity | 61 l (16.11 US gal | 13.42 UK gal) |
| Max. roof load | 75 kg (165.35 lbs.) |
| Permitted trailer load with brakes (12%) | 1600 kg (3527.4 lbs.) |
| Permitted trailer load without brakes | 745 kg (1642.44 lbs.) |
| Permitted towbar download | 75 kg (165.35 lbs.) |
| Length | 4531 mm (178.39 in.) |
| Width | 1817 mm (71.54 in.) |
| Height | 1421 mm (55.94 in.) |
| Wheelbase | 2760 mm (108.66 in.) |
| Front track | 1506 mm (59.29 in.) |
| Rear (Back) track | 1535 mm (60.43 in.) |
| Ride height (ground clearance) | 144 mm (5.67 in.) |
| Drag coefficient (Cd) | 0.27 |
| Minimum turning circle (turning diameter) | 11.0 m (36.09 ft.) |
| Drivetrain Architecture | Rear wheel drive |
| Number of gears and type of gearbox | 6 gears, automatic transmission |
| 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 | 205/55 R16 91V |
| Wheel rims size | 7J x 16 |
Powertrain & Engine Architecture
The heart of the 320d Steptronic is the N47D20C, a 2.0-liter inline-four diesel engine. This engine is a product of BMW’s advanced diesel technology, featuring common-rail direct injection and a variable geometry turbocharger. The common-rail system, operating at extremely high pressures, ensures precise fuel delivery for optimized combustion. The turbocharger, coupled with an intercooler, boosts power output and improves torque across a wide rev range. The N47 engine family was known for its efficiency and relatively low emissions, making it a popular choice in Europe. The Steptronic transmission is a six-speed automatic gearbox, offering smooth and responsive shifts. It was designed to complement the engine’s torque characteristics, providing comfortable cruising and adequate acceleration. The transmission features adaptive shift programs, adjusting to the driver’s style and road conditions.
Driving Characteristics
The 320d Steptronic delivers a refined driving experience. While not as overtly sporty as the 335i or even the 325i, it provides ample power for everyday driving and comfortable highway cruising. The 380 Nm (280 lb-ft) of torque, available from 1900-2750 rpm, provides strong pulling power, making overtaking maneuvers relatively effortless. The automatic transmission, while smooth, can feel slightly less engaging than the available six-speed manual. Compared to the manual version, the Steptronic offers convenience, especially in urban traffic, but sacrifices some driver involvement. Acceleration from 0-60 mph takes around 7.2 seconds, which is respectable for a diesel-powered sedan. The suspension setup provides a good balance between comfort and handling, typical of BMW’s engineering philosophy.
Equipment & Trim Levels
The 320d Steptronic typically came equipped with a solid base of standard features. These included automatic climate control, power windows and mirrors, a multi-function steering wheel, and a basic audio system. Upholstery was generally cloth, although leather options were available. The LCI facelift brought subtle interior revisions, including updated trim materials and improved infotainment options. Optional extras included a premium sound system, navigation system, sunroof, and sport seats. The 320d was often seen as a stepping stone into the 3 Series range, and as such, it didn’t receive the same level of standard luxury as the higher-end models like the 335i.
Chassis & Braking
The E90 3 Series features a robust chassis with independent suspension all around. The front suspension utilizes MacPherson struts, while the rear employs a multi-link setup. This configuration provides excellent ride quality and handling characteristics. The 320d Steptronic typically came equipped with ventilated disc brakes on all four wheels, providing ample stopping power. ABS (Anti-lock Braking System) was standard, enhancing safety and stability during emergency braking. The weight distribution is relatively balanced, contributing to the car’s neutral handling characteristics. Stabilizer bars were fitted front and rear to reduce body roll during cornering.
Market Reception & Comparison
The 320d Steptronic was well-received in European markets, where diesel engines were preferred for their fuel efficiency and low running costs. Critics praised its comfortable ride, refined engine, and practical nature. However, some reviewers noted that the automatic transmission could feel slightly sluggish compared to the manual. Compared to the 325i or 335i, the 320d offered less outright performance but significantly better fuel economy. The 320d also represented a more affordable entry point into the 3 Series range, making it an attractive option for budget-conscious buyers. Its fuel economy figures of around 44.4 US mpg combined were a major selling point.
Legacy
The N47 engine family, including the N47D20C found in the 320d, has proven to be generally reliable, although early versions were known for timing chain issues. Regular maintenance, including oil changes and timing chain inspections, is crucial for long-term reliability. Today, the E90 320d Steptronic represents a relatively affordable entry into BMW ownership. It’s a practical and comfortable sedan that offers a good balance of performance and efficiency. While it may not be as desirable as the higher-performance models, it remains a popular choice for those seeking a well-built and reliable German sedan.
