The Alpina D4 Cabrio (F33, facelift 2017) 3.0d Switch-Tronic represents a unique blend of high-performance diesel engineering and open-top motoring. Produced between March 2017 and August 2018, this variant occupied a niche position within the broader BMW F33 4 Series Cabriolet range, offering a compelling alternative to the gasoline-powered models. Alpina, a renowned German automotive engineering company, took the already capable 4 Series and elevated it with significant powertrain and chassis upgrades, resulting in a grand tourer focused on refined performance and everyday usability. The “facelift” designation refers to the mid-cycle refresh applied to the F33 4 Series in 2017, incorporating updated styling and technology.
Technical Specifications
| Brand | Alpina |
| Model | D4 |
| Generation | D4 Cabrio (F33, facelift 2017) |
| Type (Engine) | 3.0d (350 Hp) Switch-Tronic |
| Start of production | March, 2017 |
| End of production | August, 2018 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Cabriolet |
| Seats | 4 |
| Doors | 2 |
| Fuel consumption (economy) – urban | 6.6 l/100 km (35.6 US mpg, 42.8 UK mpg, 15.2 km/l) |
| Fuel consumption (economy) – extra urban | 5.5 l/100 km (42.8 US mpg, 51.4 UK mpg, 18.2 km/l) |
| Fuel consumption (economy) – combined | 5.9 l/100 km (39.9 US mpg, 47.9 UK mpg, 16.9 km/l) |
| CO2 emissions | 155 g/km |
| Fuel Type | Diesel |
| Acceleration 0 – 100 km/h | 5 sec |
| Acceleration 0 – 62 mph | 5 sec |
| Acceleration 0 – 60 mph | 4.8 sec |
| Maximum speed | 275 km/h (170.88 mph) |
| Weight-to-power ratio | 5.2 kg/Hp, 192.8 Hp/tonne |
| Weight-to-torque ratio | 2.6 kg/Nm, 385.7 Nm/tonne |
| Power | 350 Hp @ 4000 rpm |
| Power per litre | 116.9 Hp/l |
| Torque | 700 Nm @ 1500-3000 rpm (516.29 lb.-ft. @ 1500-3000 rpm) |
| Engine layout | Front, Longitudinal |
| Engine displacement | 2993 cm3 (182.64 cu. in.) |
| Number of cylinders | 6 |
| 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 | BiTurbo, Intercooler |
| Kerb Weight | 1815 kg (4001.39 lbs.) |
| Max. weight | 2265 kg (4993.47 lbs.) |
| Max load | 450 kg (992.08 lbs.) |
| Trunk (boot) space – maximum | 220-370 l (7.77 – 13.07 cu. ft.) |
| Fuel tank capacity | 57 l (15.06 US gal | 12.54 UK gal) |
| Permitted trailer load with brakes (12%) | 1800 kg (3968.32 lbs.) |
| Permitted trailer load without brakes | 750 kg (1653.47 lbs.) |
| Length | 4640 mm (182.68 in.) |
| Width | 1825 mm (71.85 in.) |
| Height | 1378 mm (54.25 in.) |
| Wheelbase | 2810 mm (110.63 in.) |
| Front track | 1552 mm (61.1 in.) |
| Rear (Back) track | 1576 mm (62.05 in.) |
| 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 Switch Tronic |
| 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 wheel tires: 245/35 ZR19 Rear wheel tires: 265/35 ZR19 |
| Wheel rims size | Front wheel rims: 8J x 19 Rear wheel rims: 9J x 19 |
Powertrain & Engine Architecture
At the heart of the D4 Cabrio lies Alpina’s meticulously engineered 3.0-liter inline-six diesel engine. Based on the BMW N57 engine family, Alpina significantly modified the powerplant with two specially developed turbochargers, a larger intercooler, and a revised engine management system. The engine utilizes a Bosch common-rail direct injection system, delivering fuel at pressures up to 2,500 bar for optimized combustion. The engine produces 350 horsepower at 4,000 rpm and a substantial 700 Nm (516 lb-ft) of torque available from just 1,500 rpm, providing effortless acceleration. The “Switch-Tronic” transmission is an 8-speed automatic, also based on the ZF 8HP series, but with Alpina-specific software calibration for quicker shifts and more responsive behavior. This transmission offers both automatic and manual shift modes, allowing the driver to tailor the driving experience.
Driving Characteristics
The D4 Cabrio 3.0d Switch-Tronic delivers a remarkably smooth and refined driving experience. The abundant low-end torque makes overtaking effortless, and the engine pulls strongly throughout the rev range. While not as overtly sporty as the gasoline-powered 4 Series variants, the D4 offers a unique blend of performance and efficiency. The Switch-Tronic transmission contributes to this, providing seamless gear changes and a comfortable ride. Compared to the standard 420d or 430d models, the Alpina D4 offers a significant power upgrade and a more luxurious feel. The gear ratios are tuned for both acceleration and fuel economy, providing a balance between performance and efficiency.
Equipment & Trim Levels
The Alpina D4 Cabrio was typically well-equipped, building upon the already generous standard features of the BMW 4 Series Cabriolet. Standard features included leather upholstery, heated front seats, a premium sound system, and a comprehensive suite of driver-assistance systems. Alpina-specific touches included unique interior trim pieces, Alpina badging, and a bespoke steering wheel. Optional extras included adaptive suspension, upgraded leather options, and a variety of customization options through Alpina’s Atelier program. The interior generally featured a dark wood trim and Alpina-branded gauges.
Chassis & Braking
Alpina made subtle but effective changes to the chassis to complement the increased power output. The suspension was retuned with stiffer springs and dampers, while the anti-roll bars were upgraded for improved handling. The D4 Cabrio featured ventilated disc brakes on all four wheels, providing ample stopping power. The standard ABS (Anti-lock Braking System) and stability control systems further enhanced safety. The car’s weight distribution was carefully managed to ensure balanced handling characteristics.
Market Reception & Comparison
The Alpina D4 Cabrio was generally well-received by automotive critics, who praised its blend of performance, luxury, and refinement. It was seen as a compelling alternative to the more mainstream 4 Series Cabriolet models, offering a unique and exclusive driving experience. Fuel economy was a strong point, with the D4 achieving respectable figures for a high-performance convertible. Compared to the gasoline-powered 4 Series variants, the D4 offered superior fuel efficiency and a more relaxed driving experience. However, some critics noted that the diesel engine lacked the aural excitement of a gasoline engine.
Legacy
The Alpina D4 Cabrio (F33, facelift 2017) 3.0d Switch-Tronic remains a relatively rare and sought-after vehicle in the used car market. The robust diesel engine and well-engineered transmission have proven to be reliable, making it a practical choice for those seeking a high-performance convertible. The Alpina’s exclusivity and unique character contribute to its enduring appeal. While maintenance costs may be higher than those of a standard 4 Series Cabriolet due to the specialized components, the D4 offers a rewarding ownership experience for enthusiasts who appreciate its blend of performance, luxury, and engineering excellence.
