The BMW 3 Series Sedan (F30) 318d Steptronic, produced from 2012 to 2015, represented an entry point into the sixth generation (F30) of BMW’s iconic 3 Series. This variant, powered by a 2.0-liter turbocharged diesel engine producing 143 horsepower, was primarily aimed at the European market where diesel engines held significant popularity due to fuel efficiency and tax incentives. The “Steptronic” designation indicates the inclusion of BMW’s 8-speed automatic transmission. Within the F30 lineup, the 318d served as the base diesel model, positioned below the more powerful 320d and 330d variants, and offered a balance of economy and practicality for everyday driving.
Technical Specifications
| Brand | BMW |
| Model | 3 Series |
| Generation | 3 Series Sedan (F30) |
| Type (Engine) | 318d (143 Hp) Steptronic |
| Start of production | 2012 |
| End of production | 2015 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 5.4 l/100 km (43.6 US mpg, 52.3 UK mpg, 18.5 km/l) |
| Fuel consumption (extra urban) | 3.9 l/100 km (60.3 US mpg, 72.4 UK mpg, 25.6 km/l) |
| Fuel consumption (combined) | 4.4-4.5 l/100 km (53.5 – 52.3 US mpg, 64.2 – 62.8 UK mpg, 22.7 – 22.2 km/l) |
| CO2 emissions | 117-118 g/km |
| Fuel Type | Diesel |
| Acceleration 0 – 100 km/h | 9.2 sec |
| Acceleration 0 – 62 mph | 9.2 sec |
| Acceleration 0 – 60 mph | 8.7 sec |
| Maximum speed | 212 km/h (131.73 mph) |
| Emission standard | Euro 5 |
| Weight-to-power ratio | 10 kg/Hp, 100 Hp/tonne |
| Weight-to-torque ratio | 4.5 kg/Nm, 223.8 Nm/tonne |
| Power | 143 Hp @ 4000 rpm |
| Power per litre | 71.7 Hp/l |
| Torque | 320 Nm @ 1750-2500 rpm (236.02 lb.-ft. @ 1750-2500 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 | Twin-power turbo, Intercooler |
| Engine oil capacity | 5.2 l (5.49 US qt | 4.58 UK qt) |
| Coolant | 7 l (7.4 US qt | 6.16 UK qt) |
| Kerb Weight | 1430 kg (3152.61 lbs.) |
| Max. weight | 1980 kg (4365.15 lbs.) |
| Max load | 550 kg (1212.54 lbs.) |
| Trunk (boot) space – minimum | 480 l (16.95 cu. ft.) |
| Fuel tank capacity | 57 l (15.06 US gal | 12.54 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 | 4624 mm (182.05 in.) |
| Width | 1811 mm (71.3 in.) |
| Height | 1429 mm (56.26 in.) |
| Wheelbase | 2810 mm (110.63 in.) |
| Front track | 1543 mm (60.75 in.) |
| Rear (Back) track | 1583 mm (62.32 in.) |
| Ride height (ground clearance) | 140 mm (5.51 in.) |
| Drag coefficient (Cd) | 0.26 |
| Minimum turning circle (turning diameter) | 11.3 m (37.07 ft.) |
| Drivetrain Architecture | The Internal combustion engine (ICE) drives the rear wheels of the vehicle. |
| Drive wheel | Rear wheel drive |
| Number of gears and type of gearbox | 8 gears, automatic transmission Steptronic |
| 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 | 205/60 R16 92W; 225/55 R16; 225/50 R17; 255/45 R17; 225/45 R18; 255/40 R18; 225/40 R19; 255/35 R19 |
| Wheel rims size | 7J x 16; 7.5J x 16; 7.5J x 17; 8.5J x 17; 8J x 18; 8.5J x 18; 8J x 19; 8.5J x 19 |
Powertrain & Engine Architecture
The heart of the 318d Steptronic is the BMW N47D20C engine, a 2.0-liter inline-four cylinder diesel. This engine is a member of BMW’s highly regarded N47 family, known for its efficiency and refinement. The N47D20C utilizes a second-generation common rail direct injection system, delivering fuel at pressures up to 1800 bar for optimized combustion. A single twin-scroll turbocharger with variable geometry turbine (VGT) technology provides boost, contributing to the engine’s 320 Nm (236 lb-ft) of torque available from 1750-2500 rpm. The engine also features an intercooler to further enhance performance. The Steptronic transmission is an 8-speed automatic, offering smooth and quick shifts. It’s programmed for both fuel efficiency and responsive acceleration, adapting to driving style and conditions. The transmission’s gear ratios are tuned to maximize the engine’s torque output, providing adequate acceleration without excessive engine speed.
Driving Characteristics
The 318d Steptronic delivers a comfortable and refined driving experience. While not a performance-oriented model, the 143 horsepower and 320 Nm of torque provide sufficient power for everyday driving and highway cruising. Acceleration from 0-60 mph takes approximately 8.7 seconds, and top speed is limited to 131.73 mph. The 8-speed automatic transmission contributes to smooth gear changes and helps keep the engine in its optimal power band. Compared to the manual transmission version, the Steptronic offers greater convenience, particularly in urban traffic. However, some drivers may find the automatic slightly less engaging than the manual. Compared to the more powerful 320d, the 318d feels noticeably less brisk, especially during overtaking maneuvers. The suspension is tuned for comfort, providing a compliant ride over most road surfaces.
Equipment & Trim Levels
The 318d Steptronic typically came equipped with a respectable level of standard features. These included automatic climate control, power windows and mirrors, a multi-function steering wheel, and a basic audio system. Upholstery was typically cloth, although leather options were available. Optional extras included a navigation system, upgraded audio systems (Harman Kardon), sunroof, parking sensors, and various driver assistance systems. Trim levels varied slightly depending on the market, but generally, the 318d was positioned as the entry-level diesel model, offering a good balance of features and affordability.
Chassis & Braking
The F30 3 Series utilizes a MacPherson strut front suspension and a multi-link rear suspension, providing a good balance of ride comfort and handling. The 318d, being the base model, typically featured smaller wheels and tires compared to the higher-spec variants. Braking systems consisted of ventilated disc brakes on all four wheels, providing adequate stopping power. Anti-lock Braking System (ABS) and Electronic Stability Control (ESC) were standard safety features. The chassis is relatively lightweight, contributing to the car’s agility and fuel efficiency.
Market Reception & Comparison
The 318d Steptronic was well-received in Europe as a practical and economical option within the 3 Series range. Critics praised its fuel efficiency and comfortable ride, but some noted its lack of outright performance compared to the more powerful diesel models. Fuel economy figures of around 53.5 mpg (combined) were a major selling point. Compared to the 320d, the 318d offered a lower purchase price but sacrificed some performance. The 318d also provided a more economical alternative to the gasoline-powered 320i and 328i models.
Legacy
The N47D20C engine, while generally reliable, has been known to exhibit some issues with timing chain wear, particularly in earlier production years. Regular oil changes and preventative maintenance are crucial for ensuring long-term reliability. Today, the F30 318d Steptronic represents a relatively affordable entry point into BMW ownership. Well-maintained examples can still provide years of reliable service, offering a comfortable and economical driving experience. The car’s reputation for fuel efficiency and practicality continues to make it a popular choice in the used car market, particularly for drivers seeking a balance of economy and BMW’s renowned driving dynamics.
