Technical Specifications
| Brand | BMW |
| Model | 4 Series |
| Generation | 4 Series Gran Coupe (F36, facelift 2017) |
| Type (Engine) | 420i (184 Hp) Steptronic |
| Start of production | 2017 |
| End of production | 2021 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Coupe |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 7.1-7.6 l/100 km (33.1 – 30.9 US mpg, 39.8 – 37.2 UK mpg, 14.1 – 13.2 km/l) |
| Fuel consumption (extra urban) | 4.5-4.7 l/100 km (52.3 – 50 US mpg, 62.8 – 60.1 UK mpg, 22.2 – 21.3 km/l) |
| Fuel consumption (combined) | 5.5-5.8 l/100 km (42.8 – 40.6 US mpg, 51.4 – 48.7 UK mpg, 18.2 – 17.2 km/l) |
| CO2 emissions | 127-134 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 7.7 sec |
| Acceleration 0 – 62 mph | 7.7 sec |
| Acceleration 0 – 60 mph | 7.3 sec |
| Maximum speed | 236 km/h (146.64 mph) |
| Emission standard | Euro 6 |
| Weight-to-power ratio | 8.4 kg/Hp, 119.5 Hp/tonne |
| Weight-to-torque ratio | 5.7 kg/Nm, 175.3 Nm/tonne |
| Power | 184 Hp @ 5000 rpm |
| Torque | 270 Nm @ 1350-4600 rpm (199.14 lb.-ft. @ 1350-4600 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | B48B20A |
| Engine displacement | 1998 cm3 (121.93 cu. in.) |
| Number of cylinders | 4 |
| Engine configuration | Inline |
| Cylinder Bore | 82 mm (3.23 in.) |
| Piston Stroke | 94.6 mm (3.72 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 | 5.25 l (5.55 US qt | 4.62 UK qt) |
| Coolant | 8.1 l (8.56 US qt | 7.13 UK qt) |
| Kerb Weight | 1540 kg (3395.12 lbs.) |
| Max. weight | 2100 kg (4629.71 lbs.) |
| Max load | 560 kg (1234.59 lbs.) |
| Trunk (boot) space – minimum | 480 l (16.95 cu. ft.) |
| Trunk (boot) space – maximum | 1300 l (45.91 cu. ft.) |
| Fuel tank capacity | 60 l (15.85 US gal | 13.2 UK gal) |
| Max. roof load | 75 kg (165.35 lbs.) |
| Permitted trailer load with brakes (12%) | 1500 kg (3306.93 lbs.) |
| Permitted trailer load without brakes | 695 kg (1532.21 lbs.) |
| Permitted towbar download | 75 kg (165.35 lbs.) |
| Length | 4640 mm (182.68 in.) |
| Width | 1825 mm (71.85 in.) |
| Height | 1389 mm (54.69 in.) |
| Wheelbase | 2810 mm (110.63 in.) |
| Front track | 1545 mm (60.83 in.) |
| Rear (Back) track | 1592 mm (62.68 in.) |
| Ride height (ground clearance) | 130 mm (5.12 in.) |
| Drag coefficient (Cd) | 0.29 |
| 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 |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Electric Steering |
| Tires size | 225/50 R17; 225/45 R18; 255/40 R18; 225/40 R19; 255/35 R19 |
| Wheel rims size | 7.5J x 17; 8J x 18; 8.5J x 18; 8J x 19; 8.5J x 19 |
The BMW 420i Gran Coupe Steptronic (F36, facelift) is a four-door coupe that debuted in 2017 as part of the F36 LCI (Life Cycle Impulse) update. Built on the BMW 4 Series platform, which itself is based on the F30 3 Series, the Gran Coupe offers a more stylish and practical alternative to the traditional sedan. The 420i variant, powered by the B48 2.0-liter turbocharged four-cylinder engine and paired with an 8-speed Steptronic automatic transmission, was designed to appeal to buyers seeking a balance between performance, efficiency, and comfort. It occupied a crucial position in the lineup, serving as the entry-level petrol engine option, positioned below the more powerful 430i and 440i models.
Powertrain & Engine Architecture
At the heart of the 420i Gran Coupe lies the BMW B48B20A 2.0-liter inline-four cylinder engine. This engine is a member of BMW’s modular engine family, known for its efficiency and responsiveness. It utilizes direct fuel injection, a single twin-scroll turbocharger, and variable valve timing (VANOS) and valve lift (Valvetronic) technologies to optimize power delivery and fuel economy. The B48 engine produces 184 horsepower at 5000 rpm and 270 Nm (199 lb-ft) of torque between 1350 and 4600 rpm. The 8-speed Steptronic automatic transmission is a torque-converter type, offering smooth and quick shifts. It features adaptive shift programs that adjust to the driver’s style and driving conditions. The transmission also includes a manual shift mode for greater driver control.
Driving Characteristics
The 420i Steptronic delivers a comfortable and refined driving experience. While not as overtly sporty as its higher-powered siblings, it provides ample power for everyday driving and highway cruising. The 0-60 mph acceleration time of around 7.3 seconds is respectable, and the engine’s broad torque curve ensures responsive acceleration in most situations. The 8-speed automatic transmission contributes to smooth gear changes and helps to keep the engine in its optimal power band. Compared to the 6-speed manual transmission available on some 420i models, the Steptronic offers greater convenience and ease of use, particularly in urban traffic. However, some enthusiasts may find the automatic transmission less engaging than a manual gearbox. The rear-wheel-drive configuration provides a balanced handling feel, although it can be less forgiving in slippery conditions compared to all-wheel-drive variants.
Equipment & Trim Levels
The 420i Gran Coupe Steptronic came standard with a comprehensive list of features, including automatic climate control, power-adjustable front seats, a BMW iDrive infotainment system with a 6.5-inch display screen, and a suite of safety features such as ABS, stability control, and airbags. Optional extras included a larger iDrive display screen, navigation system, premium audio system, leather upholstery, heated front seats, and a sunroof. Trim levels varied depending on the market, but generally included Sport Line, Luxury Line, and M Sport packages, each offering unique styling and equipment enhancements. The Sport Line added sporty exterior and interior accents, while the Luxury Line focused on a more refined and elegant appearance. The M Sport package included more aggressive styling cues, sport suspension, and upgraded brakes.
Chassis & Braking
The F36 4 Series Gran Coupe features a sophisticated chassis design that prioritizes both comfort and handling. The front suspension utilizes independent coil springs and struts, while the rear suspension employs an independent multi-link setup. This configuration provides a smooth ride and precise handling characteristics. The 420i Gran Coupe typically came equipped with ventilated disc brakes at the front and solid disc brakes at the rear. ABS (Anti-lock Braking System) and stability control are standard features, enhancing safety and control in various driving conditions. The steering system is a rack-and-pinion type with electric power assistance, providing precise and responsive steering feel.
Market Reception & Comparison
The 420i Gran Coupe Steptronic was generally well-received by automotive critics. It was praised for its stylish design, comfortable ride, and fuel efficiency. However, some reviewers noted that the engine lacked the outright performance of its more powerful counterparts. Compared to the 430i and 440i models, the 420i offered a more affordable entry point into the 4 Series Gran Coupe range, but at the expense of performance. In terms of fuel economy, the 420i outperformed the higher-powered models, achieving combined fuel consumption figures of around 40-43 mpg. Reliability has been generally good, with the B48 engine proving to be a robust and dependable unit. However, like all BMWs, regular maintenance is essential to ensure long-term reliability.
Legacy
The BMW 420i Gran Coupe Steptronic (F36) remains a popular choice in the used car market. Its combination of style, practicality, and fuel efficiency continues to appeal to buyers seeking a premium compact executive car. The B48 engine has proven to be a reliable powerplant, and the 8-speed Steptronic automatic transmission is known for its smooth operation. While not the most exciting model in the 4 Series lineup, the 420i Gran Coupe offers a compelling value proposition for those prioritizing comfort, efficiency, and a refined driving experience. Its enduring appeal is a testament to BMW’s engineering prowess and its ability to create cars that are both enjoyable to drive and practical for everyday use.
