The BMW 4 Series Convertible (F33), specifically the 440i variant with the Steptronic automatic transmission, represents a compelling blend of performance and open-air luxury. Produced from 2017 to 2020 as part of the F33 lifecycle facelift, this model occupied a premium position within the 4 Series range, offering a significant step up in power and refinement compared to the 420i and 430i models. It served as a direct competitor to other premium convertible grand tourers like the Audi A5 Cabriolet and Mercedes-Benz C-Class Cabriolet, appealing to buyers seeking a sporty yet comfortable driving experience.
Technical Specifications
| Brand | BMW |
| Model | 4 Series |
| Generation | 4 Series Convertible (F33, facelift 2017) |
| Type (Engine) | 440i (326 Hp) Steptronic |
| Start of production | 2017 |
| End of production | 2020 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Cabriolet |
| Seats | 4 |
| Doors | 2 |
| Fuel consumption (urban) | 9.1-9.5 l/100 km (25.8 – 24.8 US mpg, 31 – 29.7 UK mpg, 11 – 10.5 km/l) |
| Fuel consumption (extra urban) | 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) |
| Fuel consumption (combined) | 6.8-7.2 l/100 km (34.6 – 32.7 US mpg, 41.5 – 39.2 UK mpg, 14.7 – 13.9 km/l) |
| CO2 emissions | 159-167 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 5.4 sec |
| Acceleration 0 – 62 mph | 5.4 sec |
| Acceleration 0 – 60 mph | 5.1 sec |
| Maximum speed | 250 km/h (155.34 mph) |
| Emission standard | Euro 6 |
| Weight-to-power ratio | 5.4 kg/Hp, 184.2 Hp/tonne |
| Weight-to-torque ratio | 3.9 kg/Nm, 254.2 Nm/tonne |
| Power | 326 Hp @ 5500 rpm |
| Power per litre | 108.7 Hp/l |
| Torque | 450 Nm @ 1380-5000 rpm (331.9 lb.-ft. @ 1380-5000 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | B58B30A |
| Engine displacement | 2998 cm3 (182.95 cu. in.) |
| Number of cylinders | 6 |
| 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 | 6.5 l (6.87 US qt | 5.72 UK qt) |
| Coolant | 9.3 l (9.83 US qt | 8.18 UK qt) |
| Kerb Weight | 1770 kg (3902.18 lbs.) |
| Max. weight | 2230 kg (4916.31 lbs.) |
| Max load | 460 kg (1014.13 lbs.) |
| Trunk (boot) space – minimum | 370 l (13.07 cu. ft.) |
| Fuel tank capacity | 60 l (15.85 US gal | 13.2 UK gal) |
| Permitted trailer load with brakes (12%) | 1700 kg (3747.86 lbs.) |
| Permitted trailer load without brakes | 750 kg (1653.47 lbs.) |
| Permitted towbar download | 75 kg (165.35 lbs.) |
| Length | 4640 mm (182.68 in.) |
| Width | 1825 mm (71.85 in.) |
| Height | 1384 mm (54.49 in.) |
| Wheelbase | 2810 mm (110.63 in.) |
| Front track | 1544 mm (60.79 in.) |
| Rear (Back) track | 1593 mm (62.72 in.) |
| Ride height (ground clearance) | 130 mm (5.12 in.) |
| Drag coefficient (Cd) | 0.30 |
| 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 | 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 |
Powertrain & Engine Architecture
At the heart of the 440i Convertible lies BMW’s B58B30A 3.0-liter inline-six engine. This engine is a cornerstone of BMW’s modern powertrain strategy, known for its smooth power delivery and efficiency. The ‘B58’ designation indicates its position within BMW’s modular engine family. It utilizes direct fuel injection, operating at a compression ratio of 11:1, and is equipped with a twin-scroll turbocharger and intercooler. This configuration allows for a broad torque curve, peaking at 450 Nm (331.9 lb-ft) between 1380 and 5000 rpm. The engine produces 326 horsepower at 5500 rpm. The Steptronic 8-speed automatic transmission is integral to the driving experience. This transmission features adaptive shift programs, allowing it to adjust to the driver’s style and road conditions. It offers both automatic and manual shift modes, with paddle shifters available for more driver involvement.
Driving Characteristics
The 440i Convertible’s driving experience is characterized by a refined yet engaging character. The combination of the potent inline-six and the 8-speed automatic results in brisk acceleration – 0 to 60 mph in approximately 5.1 seconds. The Steptronic transmission provides smooth and quick gear changes, contributing to a seamless power delivery. Compared to the 420i or 430i models, the 440i offers a noticeably more responsive and powerful experience. While not as raw or focused as a dedicated sports car, the 440i strikes a good balance between performance and comfort, making it well-suited for both spirited driving and long-distance cruising. The rear-wheel-drive configuration contributes to a balanced chassis, enhancing handling and cornering ability.
Equipment & Trim Levels
The 440i Convertible typically came well-equipped as standard. Features included leather upholstery, power-adjustable seats with memory function, a premium sound system, and BMW’s iDrive infotainment system with a central display screen. Common options included a head-up display, navigation system, adaptive cruise control, and upgraded interior trim materials. The convertible top was a fully automatic, retractable hardtop, offering good insulation and security when raised. Interior color choices were extensive, allowing for a degree of personalization. Exterior options included various wheel designs, paint colors, and aerodynamic enhancements.
Chassis & Braking
The F33 4 Series Convertible utilizes a sophisticated chassis design. The front suspension features independent coil springs, while the rear employs an independent multi-link setup. This configuration provides a comfortable ride while maintaining good handling characteristics. The 440i typically came equipped with 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. The steering system is a rack-and-pinion setup with electric power assistance, offering precise and responsive steering feel.
Market Reception & Comparison
The 440i Convertible was generally well-received by automotive critics. Reviewers praised its powerful engine, refined ride, and luxurious interior. The Steptronic transmission was also lauded for its smooth operation. Compared to the 420i and 430i, the 440i offered a significant performance upgrade, justifying its higher price tag. Fuel economy, while not exceptional, was reasonable for a performance-oriented convertible, averaging around 34.6 – 32.7 US mpg in combined driving. Reliability reports have been generally positive, with the B58 engine proving to be a robust and dependable unit.
Legacy
The BMW 440i Convertible (F33) has established itself as a desirable used car. The B58 engine’s reputation for reliability and performance continues to attract buyers. The combination of a powerful engine, comfortable interior, and stylish design makes it a compelling option in the used luxury convertible market. Well-maintained examples command a premium price, reflecting their enduring appeal. The F33 generation, and particularly the 440i variant, represents a high point in BMW’s convertible offerings, blending performance, luxury, and driving enjoyment in a compelling package.
