The BMW 3 Series Sedan (F30 LCI), specifically the 318d variant with the Steptronic automatic transmission, was produced from 2015 to 2018. This model represents a mid-cycle refresh of the sixth-generation 3 Series (F30), introducing updated styling, improved efficiency, and revised engine options. The 318d Steptronic occupied the entry-level position in the 3 Series diesel lineup, offering a balance of fuel economy, reasonable performance, and BMW’s characteristic driving dynamics. It was primarily marketed in Europe and other regions where diesel engines were popular, offering a compelling alternative to gasoline-powered models.
Technical Specifications
| Brand | BMW |
| Model | 3 Series |
| Generation | 3 Series Sedan (F30 LCI, Facelift 2015) |
| Type (Engine) | 318d (150 Hp) Steptronic |
| Start of production | 2015 |
| End of production | 2018 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (economy) – urban (NEDC) | 4.8-5.3 l/100 km (49 – 44.4 US mpg, 58.9 – 53.3 UK mpg, 20.8 – 18.9 km/l) |
| Fuel consumption (economy) – extra urban (NEDC) | 3.6-3.9 l/100 km (65.3 – 60.3 US mpg, 78.5 – 72.4 UK mpg, 27.8 – 25.6 km/l) |
| Fuel consumption (economy) – combined (NEDC) | 4-4.4 l/100 km (58.8 – 53.5 US mpg, 70.6 – 64.2 UK mpg, 25 – 22.7 km/l) |
| CO2 emissions (NEDC) | 106-116 g/km |
| Fuel Type | Diesel |
| Acceleration 0 – 100 km/h | 8.4 sec |
| Acceleration 0 – 62 mph | 8.4 sec |
| Acceleration 0 – 60 mph | 8 sec (Calculated) |
| Maximum speed | 212 km/h (131.73 mph) |
| Emission standard | Euro 6 |
| Weight-to-power ratio | 9.7 kg/Hp, 103.4 Hp/tonne |
| Weight-to-torque ratio | 4.5 kg/Nm, 220.7 Nm/tonne |
| Power | 150 Hp @ 4000 rpm |
| Torque | 320 Nm @ 1500-3000 rpm (236.02 lb.-ft. @ 1500-3000 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | B47D20A |
| 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 |
| Valvetrain | DOHC |
| Engine oil capacity | 5 l (5.28 US qt | 4.4 UK qt) |
| Coolant | 7 l (7.4 US qt | 6.16 UK qt) |
| Kerb Weight | 1450 kg (3196.7 lbs.) |
| Max. weight | 2070 kg (4563.57 lbs.) |
| Max load | 620 kg (1366.87 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%) | 1800 kg (3968.32 lbs.) |
| Permitted trailer load without brakes | 745 kg (1642.44 lbs.) |
| Permitted towbar download | 75 kg (165.35 lbs.) |
| Length | 4633 mm (182.4 in.) |
| Width | 1811 mm (71.3 in.) |
| Width including mirrors | 2031 mm (79.96 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.) |
| Front overhang | 779 mm (30.67 in.) |
| Rear overhang | 1044 mm (41.1 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 | Rear wheel drive |
| Number of gears and type of gearbox | 8 gears, automatic transmission Steptronic |
| Front suspension | Spring Strut, Transverse stabilizer |
| Rear suspension | Independent multi-link spring suspension with stabilizer |
| 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 | Front: 205/60 R16, 225/50 R17, 225/45 R18, 225/45 R19; Rear: 205/60 R16, 225/50 R17, 225/45 R18, 255/40 R18, 255/35 R19 |
| Wheel rims size | Front: 7J x 16, 7.5J x 17, 8J x 18, 8J x 19; Rear: 7J x 16, 7.5J x 17, 8J x 18, 8.5J x 18, 8.5J x 19 |
Powertrain & Engine Architecture
The 318d Steptronic is powered by the BMW B47D20A, a 2.0-liter inline-four diesel engine. This engine is part of BMW’s modular engine family, known for its efficiency and refinement. The B47 utilizes a common-rail direct injection system, delivering fuel at extremely high pressure for optimized combustion. A twin-scroll turbocharger with intercooling enhances power output and reduces turbo lag. The engine also features variable valve timing (DOHC) and a 16.5:1 compression ratio. The Steptronic transmission is an 8-speed automatic gearbox, offering smooth and efficient gear changes. It features adaptive shift programs that adjust to the driver’s style and road conditions. This transmission was a significant upgrade over older automatic transmissions, contributing to improved fuel economy and performance.
Driving Characteristics
The 318d Steptronic delivers a comfortable and refined driving experience. While not as overtly sporty as higher-powered 3 Series variants, it provides adequate acceleration for everyday driving. The 320 Nm (236 lb-ft) of torque, available from 1500-3000 rpm, provides good responsiveness in most situations. The 8-speed Steptronic transmission is well-matched to the engine, offering smooth upshifts and downshifts. Compared to the 6-speed manual transmission available on some 318d models, the Steptronic prioritizes comfort and ease of use over outright driver engagement. Acceleration from 0 to 100 km/h (0-62 mph) takes 8.4 seconds, and the top speed is 212 km/h (131.73 mph). The rear-wheel-drive configuration contributes to the 3 Series’ balanced handling characteristics.
Equipment & Trim Levels
The 318d Steptronic typically came equipped with a respectable level of standard features. These included automatic climate control, a BMW iDrive infotainment system with a central display screen, power windows and mirrors, and a multi-function steering wheel. Interior upholstery was typically cloth, with leather options available as an upgrade. Common optional extras included a sunroof, navigation system, upgraded audio system, and parking sensors. Trim levels varied depending on the market, but generally offered packages that added features like sport seats, alloy wheels, and exterior styling enhancements.
Chassis & Braking
The F30 3 Series features a MacPherson strut front suspension and a multi-link rear suspension. The 318d variant typically used a slightly softer suspension setup compared to higher-performance models, prioritizing ride comfort. Stabilizer bars were fitted to both the front and rear axles to reduce body roll. The braking system consisted of ventilated disc brakes on all four wheels, providing ample stopping power. Anti-lock braking system (ABS) and electronic stability control (ESC) were standard safety features.
Market Reception & Comparison
The 318d Steptronic was generally well-received by automotive critics as a practical and efficient option within the 3 Series range. It was praised for its fuel economy, comfortable ride, and refined engine. However, some reviewers noted that it lacked the outright performance of higher-powered models like the 320d or 330i. Compared to the 320d, the 318d offered lower running costs but less power and acceleration. The 318d was often seen as a sensible choice for drivers who prioritized fuel efficiency and comfort over sporty driving dynamics.
Legacy
The B47 engine, found in the 318d Steptronic, has proven to be a relatively reliable powertrain. While some early B47 engines experienced issues with timing chain wear, these were largely addressed in later revisions. The 8-speed Steptronic transmission has also proven to be durable and reliable. Today, used examples of the 318d Steptronic are readily available and represent a good value for money, offering a comfortable and efficient driving experience. However, potential buyers should ensure that the vehicle has been properly maintained and that any known issues, such as timing chain wear, have been addressed.
