The BMW 6 Series Gran Turismo (G32) 640i xDrive Steptronic represents BMW’s foray into a niche blending luxury, practicality, and performance within the Gran Turismo segment. Produced from 2017 to 2020, this model aimed to offer a more spacious and versatile alternative to the traditional 6 Series coupe and convertible. Built on the G32 platform, it distinguished itself with a hatchback design and a focus on rear passenger comfort. The 640i, positioned as a mid-to-high range offering within the Gran Turismo lineup, combined a potent inline-six engine with BMW’s xDrive all-wheel-drive system and the Steptronic eight-speed automatic transmission.
Technical Specifications
| Brand | BMW |
| Model | 6 Series |
| Generation | 6 Series Gran Turismo (G32) |
| Type (Engine) | 640i (340 Hp) xDrive Steptronic |
| Start of production | 2017 |
| End of production | 2020 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Grand Tourer |
| Seats | 5 |
| Doors | 5 |
| Fuel consumption (economy) – urban | 10.5-11.1 l/100 km (22.4 – 21.2 US mpg, 26.9 – 25.4 UK mpg, 9.5 – 9 km/l) |
| Fuel consumption (economy) – extra urban | 6.1-6.5 l/100 km (38.6 – 36.2 US mpg, 46.3 – 43.5 UK mpg, 16.4 – 15.4 km/l) |
| Fuel consumption (economy) – combined | 7.7-8.2 l/100 km (30.5 – 28.7 US mpg, 36.7 – 34.4 UK mpg, 13 – 12.2 km/l) |
| CO2 emissions | 177-187 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 5.3 sec |
| Acceleration 0 – 62 mph | 5.3 sec |
| Acceleration 0 – 60 mph | 5 sec |
| Maximum speed | 250 km/h (155.34 mph) |
| Emission standard | Euro 6 |
| Weight-to-power ratio | 5.4 kg/Hp, 185.3 Hp/tonne |
| Weight-to-torque ratio | 4.1 kg/Nm, 245.2 Nm/tonne |
| Power | 340 Hp @ 5500-6500 rpm |
| Power per litre | 113.4 Hp/l |
| Torque | 450 Nm @ 1380-5200 rpm (331.9 lb.-ft. @ 1380-5200 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | B58B30C |
| 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 | 10.5 l (11.1 US qt | 9.24 UK qt) |
| Kerb Weight | 1835 kg (4045.48 lbs.) |
| Max. weight | 2515 kg (5544.63 lbs.) |
| Max load | 680 kg (1499.14 lbs.) |
| Trunk (boot) space – minimum | 610 l (21.54 cu. ft.) |
| Trunk (boot) space – maximum | 1800 l (63.57 cu. ft.) |
| Fuel tank capacity | 68 l (17.96 US gal | 14.96 UK gal) |
| Max. roof load | 75 kg (165.35 lbs.) |
| Permitted trailer load with brakes (12%) | 2100 kg (4629.71 lbs.) |
| Permitted trailer load without brakes | 750 kg (1653.47 lbs.) |
| Permitted towbar download | 100 kg (220.46 lbs.) |
| Length | 5091 mm (200.43 in.) |
| Width | 1902 mm (74.88 in.) |
| Width including mirrors | 2158 mm (84.96 in.) |
| Height | 1540 mm (60.63 in.) |
| Wheelbase | 3070 mm (120.87 in.) |
| Front track | 1615 mm (63.58 in.) |
| Rear (Back) track | 1647 mm (64.84 in.) |
| Front overhang | 871 mm (34.29 in.) |
| Rear overhang | 1150 mm (45.28 in.) |
| Ride height (ground clearance) | 138 mm (5.43 in.) |
| Drag coefficient (Cd) | 0.27 |
| Minimum turning circle (turning diameter) | 12.5 m (41.01 ft.) |
| Drive wheel | All wheel drive (4×4) |
| Number of gears and type of gearbox | 8 gears, automatic transmission Steptronic |
| Front suspension | Double wishbone |
| 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 | 225/60 R17; 245/50 R18; 245/45 R19; 275/40 R19; 245/40 R20; 275/35 R20 |
| Wheel rims size | 7.5J x 17; 8J x 18; 8.5J x 19; 9.5J x 19; 8.5J x 20; 10J x 20 |
Powertrain & Engine Architecture
The heart of the 640i xDrive is BMW’s B58B30C 3.0-liter inline-six engine. This engine is a member of BMW’s modular engine family, known for its smooth power delivery and efficiency. The B58 utilizes a single twin-scroll turbocharger, direct fuel injection, and Double-VANOS variable valve timing for both intake and exhaust. This combination results in a broad torque curve peaking at 450 Nm (331.9 lb-ft) between 1380 and 5200 rpm, and a maximum power output of 340 hp at 5500-6500 rpm. The engine’s longitudinal mounting and the rear-biased xDrive all-wheel-drive system contribute to balanced handling. The Steptronic eight-speed automatic transmission is a crucial component, offering smooth and quick shifts. It features adaptive shift programs that adjust to the driver’s style and road conditions.
Driving Characteristics
The 640i xDrive Steptronic delivers a refined and capable driving experience. The combination of the potent inline-six and the eight-speed automatic provides brisk acceleration, achieving 0-60 mph in approximately 5 seconds. While not as overtly sporty as some of BMW’s other models, the 640i offers ample power for comfortable highway cruising and confident overtaking. The xDrive system provides excellent traction in various weather conditions. The automatic transmission’s gear ratios are tuned for a balance of performance and fuel efficiency. Compared to the 630i, the 640i offers a noticeable increase in power and torque, resulting in a more responsive and engaging driving experience. It doesn’t match the outright performance of the 650i, but provides a compelling alternative for those prioritizing efficiency and a smoother ride.
Equipment & Trim Levels
The 640i xDrive Gran Turismo came standard with a comprehensive list of features, including leather upholstery, power-adjustable front seats with memory function, a premium sound system, and a large infotainment screen with iDrive controller. Standard safety features included automatic emergency braking, lane departure warning, and adaptive cruise control. Optional extras included a panoramic sunroof, upgraded leather options, rear-seat entertainment systems, and a head-up display. The interior design emphasized luxury and spaciousness, with a focus on rear passenger comfort. The hatchback design provides a generous amount of cargo space, making it a practical choice for families and those who frequently transport large items.
Chassis & Braking
The 6 Series Gran Turismo utilizes a double-wishbone front suspension and an independent multi-link rear suspension, providing a comfortable and controlled ride. The suspension is tuned to prioritize comfort over outright sportiness, but still offers good body control in corners. Ventilated disc brakes are fitted on all four wheels, providing ample stopping power. The electronic power steering system offers precise and responsive steering feel. The xDrive all-wheel-drive system distributes power between the front and rear axles as needed, optimizing traction and stability.
Market Reception & Comparison
The 6 Series Gran Turismo, and specifically the 640i variant, received mixed reviews from automotive critics. While praised for its spacious interior, comfortable ride, and refined powertrain, some critics found the styling unconventional and the overall driving experience less engaging than other BMW models. Compared to the 630i, the 640i offered a significant performance upgrade, justifying the higher price tag for those seeking more power. Fuel economy was generally considered good for a vehicle of its size and performance, averaging around 28.7-30.5 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 6 Series Gran Turismo (G32) represented a bold attempt to redefine the luxury Gran Turismo segment. While production ended in 2020, the 640i xDrive Steptronic remains a desirable used car option for those seeking a blend of luxury, practicality, and performance. The B58 engine is highly regarded for its reliability and tunability, making it a popular choice among enthusiasts. As a used vehicle, the 640i offers a compelling value proposition, providing a premium driving experience at a more accessible price point. Its spacious interior and versatile hatchback design continue to appeal to buyers looking for a comfortable and practical luxury vehicle.
