The BMW 6 Series Gran Coupe (F06) 640i Steptronic, produced from 2012 to 2015, represents BMW’s foray into the four-door coupe market, blending the styling of a traditional coupe with the practicality of a sedan. Positioned as a mid-range offering within the F06 Gran Coupe lineup, it sat above the 630i and below the performance-oriented 650i. This variant aimed to provide a balance of performance, luxury, and efficiency, appealing to buyers seeking a sophisticated grand tourer. The 640i utilized BMW’s then-current technology, including their Steptronic automatic transmission and turbocharged engine technology, to deliver a refined driving experience.
Technical Specifications
| Brand | BMW |
| Model | 6 Series |
| Generation | 6 Series Gran Coupe (F06) |
| Type (Engine) | 640i (320 Hp) Steptronic |
| Start of production | 2012 |
| End of production | 2015 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Coupe |
| Seats | 4 |
| Doors | 4 |
| Fuel consumption (urban) | 10.5-10.7 l/100 km (22.4 – 22 US mpg, 26.9 – 26.4 UK mpg, 9.5 – 9.3 km/l) |
| Fuel consumption (extra urban) | 6.0-6.2 l/100 km (39.2 – 37.9 US mpg, 47.1 – 45.6 UK mpg, 16.7 – 16.1 km/l) |
| Fuel consumption (combined) | 7.7-7.9 l/100 km (30.5 – 29.8 US mpg, 36.7 – 35.8 UK mpg, 13 – 12.7 km/l) |
| CO2 emissions | 179-183 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 5 |
| Weight-to-power ratio | 5.5 kg/Hp, 182.9 Hp/tonne |
| Weight-to-torque ratio | 3.9 kg/Nm, 257.1 Nm/tonne |
| Power | 320 Hp @ 5800-6000 rpm |
| Power per litre | 107.4 Hp/l |
| Torque | 450 Nm @ 1300-4500 rpm (331.9 lb.-ft. @ 1300-4500 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | N55B30A |
| Engine displacement | 2979 cm3 (181.79 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | Inline |
| Cylinder Bore | 84 mm (3.31 in.) |
| Piston Stroke | 89.6 mm (3.53 in.) |
| Compression ratio | 10.2:1 |
| 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 | 1750 kg (3858.09 lbs.) |
| Max. weight | 2360 kg (5202.91 lbs.) |
| Max load | 610 kg (1344.82 lbs.) |
| Trunk (boot) space – minimum | 460 l (16.24 cu. ft.) |
| Trunk (boot) space – maximum | 1265 l (44.67 cu. ft.) |
| Fuel tank capacity | 70 l (18.49 US gal | 15.4 UK gal) |
| Max. roof load | 75 kg (165.35 lbs.) |
| Length | 5007 mm (197.13 in.) |
| Width | 1894 mm (74.57 in.) |
| Height | 1392 mm (54.8 in.) |
| Wheelbase | 2968 mm (116.85 in.) |
| Front track | 1600 mm (62.99 in.) |
| Rear (Back) track | 1665 mm (65.55 in.) |
| Ride height (ground clearance) | 126 mm (4.96 in.) |
| Drag coefficient (Cd) | 0.29 |
| Minimum turning circle (turning diameter) | 11.95 m (39.21 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 | 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 | 225/55 R17; 245/45 R18; 245/40 R19; 275/35 R19; 245/35 R20; 275/30 R20 |
| Wheel rims size | 8J x 17; 8J x 18; 8.5J x 19; 9J x 19; 8.5J x 20; 9J x 20 |
INTRODUCTION
The BMW 640i Gran Coupe, launched in 2012, was a key component of BMW’s strategy to expand its offerings in the luxury coupe segment. Built on the F06 chassis, which shared its underpinnings with the F10 5 Series, the 640i aimed to deliver a more dynamic and stylish alternative to traditional sedans. The “Gran Coupe” designation signified BMW’s intention to create a four-door vehicle with the aesthetic appeal of a two-door coupe. The 640i, powered by the N55 engine and paired with the 8-speed Steptronic transmission, was designed to appeal to drivers who desired a blend of performance and comfort.
Powertrain & Engine Architecture
At the heart of the 640i lies the N55B30A, a 3.0-liter inline-six cylinder engine. This engine is a significant evolution of BMW’s long-standing inline-six tradition, featuring direct fuel injection, a twin-scroll turbocharger, and variable valve timing (VANOS) and valve lift (Valvetronic) technologies. The N55 engine produces 320 horsepower at 5800-6000 rpm and 450 Nm (331.9 lb-ft) of torque between 1300 and 4500 rpm. This broad torque curve contributes to strong acceleration across a wide range of engine speeds. The engine’s aluminum block and head help to reduce weight, enhancing both performance and efficiency.
The 640i exclusively utilized BMW’s 8-speed Steptronic automatic transmission. This transmission offers smooth and quick shifts, and features adaptive learning algorithms that adjust shift points based on driving style. Drivers could also manually select gears using steering wheel-mounted paddles, providing a more engaging driving experience. The transmission’s wide gear ratio spread contributes to both fuel efficiency and strong acceleration.
Driving Characteristics
The 640i Steptronic delivers a refined and capable driving experience. While not as overtly sporty as the 650i, the 640i provides ample power for both highway cruising and spirited driving. The 0-60 mph acceleration time of around 5.1 seconds is respectable, and the engine’s strong mid-range torque makes overtaking effortless. The Steptronic transmission contributes to a smooth and seamless driving experience, although some drivers may prefer the more direct engagement of a manual transmission. The Gran Coupe’s chassis, derived from the 5 Series, provides a comfortable ride without sacrificing handling precision. The steering is precise and well-weighted, offering good feedback to the driver.
Equipment & Trim Levels
The 640i Gran Coupe came standard with a comprehensive list of features, including leather upholstery, power-adjustable front seats with memory function, a premium sound system, and a navigation system. Standard exterior features included xenon headlights, 18-inch alloy wheels, and a power-operated trunk lid. Optional extras included a Bang & Olufsen sound system, active steering, adaptive suspension, and a head-up display. Interior trim options included various wood veneers and aluminum accents. The 640i could also be equipped with BMW’s ConnectedDrive services, providing access to online information and concierge services.
Chassis & Braking
The F06 Gran Coupe utilizes a double-wishbone front suspension and an independent multi-link rear suspension. This suspension setup provides a good balance of ride comfort and handling precision. The 640i typically came equipped with ventilated disc brakes on all four wheels, providing ample stopping power. Anti-lock braking system (ABS), dynamic stability control (DSC), and traction control were standard safety features. The car’s electronic power steering system provides variable assistance, adjusting steering effort based on vehicle speed.
Market Reception & Comparison
The 640i Gran Coupe was generally well-received by automotive critics. Reviewers praised its stylish design, comfortable interior, and refined driving experience. However, some critics noted that the 640i lacked the outright performance of the 650i. Compared to the 650i, the 640i offered a more affordable entry point into the 6 Series Gran Coupe range, while still providing a luxurious and capable driving experience. The 640i also offered better fuel economy than the 650i. Against competitors like the Audi A7 and Mercedes-Benz CLS, the 640i was often praised for its more engaging driving dynamics.
Legacy
The N55 engine, found in the 640i, has proven to be a reliable and durable powerplant. While some early N55 engines experienced issues with the fuel injectors and oil leaks, these problems were largely addressed in later production years. The 8-speed Steptronic transmission has also proven to be reliable, with few reported issues. Today, the F06 640i Gran Coupe represents a compelling value in the used luxury coupe market. Its combination of style, performance, and comfort makes it an attractive option for buyers seeking a sophisticated grand tourer. Maintenance costs are generally reasonable for a luxury vehicle of this caliber, although preventative maintenance is crucial to ensure long-term reliability.
