Technical Specifications
| Brand | BMW |
| Model | 4 Series |
| Generation | 4 Series Gran Coupe (F36) |
| Type (Engine) | 420i (184 Hp) Steptronic |
| Start of production | 2014 |
| End of production | 2016 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Coupe |
| Seats | 5 |
| Doors | 5 |
| Fuel consumption (urban) | 8.4 l/100 km (28 US mpg, 33.6 UK mpg, 11.9 km/l) |
| Fuel consumption (extra urban) | 5 l/100 km (47 US mpg, 56.5 UK mpg, 20 km/l) |
| Fuel consumption (combined) | 6.3 l/100 km (37.3 US mpg, 44.8 UK mpg, 15.9 km/l) |
| CO2 emissions | 146 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 7.6 sec |
| Acceleration 0 – 62 mph | 7.6 sec |
| Acceleration 0 – 60 mph | 7.2 sec |
| Maximum speed | 236 km/h (146.64 mph) |
| Emission standard | Euro 6 |
| Weight-to-power ratio | 8.6 kg/Hp, 116.5 Hp/tonne |
| Weight-to-torque ratio | 5.9 kg/Nm, 170.9 Nm/tonne |
| Power | 184 Hp @ 5000-6250 rpm |
| Power per litre | 92.1 Hp/l |
| Torque | 270 Nm @ 1250-4500 rpm (199.14 lb.-ft. @ 1250-4500 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | N20B20B |
| Engine displacement | 1997 cm3 (121.86 cu. in.) |
| Number of cylinders | 4 |
| Engine configuration | Inline |
| Cylinder Bore | 84 mm (3.31 in.) |
| Piston Stroke | 90.1 mm (3.55 in.) |
| Compression ratio | 11:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Direct injection |
| Engine aspiration | Twin-power turbo, Intercooler |
| Engine oil capacity | 5 l (5.28 US qt | 4.4 UK qt) |
| Coolant | 7.6 l (8.03 US qt | 6.69 UK qt) |
| Kerb Weight | 1580 kg (3483.3 lbs.) |
| Max. weight | 2065 kg (4552.55 lbs.) |
| Max load | 485 kg (1069.24 lbs.) |
| Fuel tank capacity | 60 l (15.85 US gal | 13.2 UK gal) |
| Length | 4638 mm (182.6 in.) |
| Width | 1825 mm (71.85 in.) |
| Height | 1389 mm (54.69 in.) |
| Wheelbase | 2810 mm (110.63 in.) |
| Front track | 1557 mm (61.3 in.) |
| Rear (Back) track | 1605 mm (63.19 in.) |
| Drivetrain Architecture | Rear wheel drive |
| 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 | 225/50 R17 94W |
| Wheel rims size | 7.5J x 17 |
The F36 420i Steptronic, produced from 2014 to 2016, represented a compelling entry point into the BMW 4 Series Gran Coupe lineup. Positioned as a more accessible variant, it offered the sleek styling and practicality of the Gran Coupe body style with a focus on fuel efficiency and comfortable cruising. This model occupied the lower-mid range of the F36 series, slotting below the more powerful 428i and 435i models, and offering a distinct alternative to the six-cylinder options. It was primarily marketed towards buyers seeking a premium four-door coupe experience without the higher price tag and performance demands of its siblings.
Powertrain & Engine Architecture
The 420i Steptronic is powered by the N20B20B 2.0-liter inline-four cylinder engine. This engine is part of BMW’s N20 family, well-regarded for its balance of performance and efficiency. It features direct fuel injection, a twin-scroll turbocharger, and variable valve timing (VANOS) and valve lift (Valvetronic) technologies to optimize power delivery and fuel economy. The engine generates 184 horsepower at 5,000-6,250 rpm and 270 Nm (199 lb-ft) of torque between 1,250 and 4,500 rpm. This broad torque curve provides responsive acceleration in typical driving scenarios.
The “Steptronic” designation refers to BMW’s 8-speed automatic transmission. This transmission is known for its smooth and quick shifts, contributing to both performance and fuel efficiency. It utilizes a torque converter and allows for both fully automatic operation and manual gear selection via steering wheel-mounted paddles or the gear selector. The transmission’s gear ratios are optimized to maximize fuel economy while still providing adequate acceleration.
Driving Characteristics
The 420i Steptronic delivers a refined and comfortable driving experience. While not as sporty as the higher-powered 4 Series variants, it offers sufficient power for everyday driving and highway cruising. Acceleration from 0 to 60 mph takes around 7.2 seconds, which is competitive for a four-door coupe in its class. The 8-speed automatic transmission contributes to smooth and seamless gear changes, enhancing the overall driving experience. Compared to the 6-speed manual transmission offered on some 420i models, the Steptronic provides greater convenience and ease of use, especially in city traffic. However, some driving enthusiasts might prefer the more engaging feel of the manual transmission.
Equipment & Trim Levels
The 420i Steptronic typically came standard with features like automatic climate control, power-adjustable front seats, a BMW iDrive infotainment system with a 6.5-inch display, and a comprehensive suite of safety features including ABS, stability control, and multiple airbags. Standard upholstery was cloth or leatherette, with leather available as an optional upgrade. Popular optional extras included a sunroof, navigation system, a premium sound system, and various driver-assistance features such as parking sensors and lane departure warning. Trim levels varied by market, but generally offered packages that bundled popular options together.
Chassis & Braking
The F36 420i Gran Coupe features a sophisticated chassis design. The front suspension utilizes independent coil springs, while the rear suspension employs an independent multi-link setup. This configuration strikes a good balance between ride comfort and handling precision. The steering is electrically assisted, offering precise and responsive control. Braking is handled by ventilated discs on all four wheels, providing ample stopping power. The ABS system helps prevent wheel lockup during hard braking, enhancing safety.
Market Reception & Comparison
The 420i Steptronic was generally well-received by automotive critics. It was praised for its stylish design, comfortable ride, and fuel efficiency. Some reviewers noted that the engine could feel somewhat underpowered, particularly when the vehicle is fully loaded or driving uphill. Compared to the 428i and 435i models, the 420i offered a more affordable entry point into the 4 Series Gran Coupe range, but at the cost of outright performance. In terms of fuel economy, the 420i consistently outperformed its more powerful siblings, making it an attractive option for buyers prioritizing efficiency.
Legacy
The N20 engine, found in the 420i Steptronic, has proven to be a relatively reliable powertrain, although some owners have reported issues with the timing chain and oil leaks. Consistent maintenance, including timely oil changes and inspections, is crucial for long-term reliability. On the used car market, the F36 420i Steptronic represents a good value, offering a stylish and well-equipped vehicle at a reasonable price. Its combination of practicality, comfort, and fuel efficiency continues to appeal to a broad range of buyers.
