The U.K. market launch of the Clubman All4 is here and we’ve got a full set of photos of MINI’s latest all wheel drive four door. We also thought this was a great time to talk a bit about what makes the All4 system special in the MINI range.
Upsides with Limited Downsides
All wheel drive is all about priories. If traction and safety is a priority over outright performance and efficiency, ALL4 should be paramount. But as we’ll find out, MINI has further reduced those traditional downsides that all wheel drive has brought. In fact performance has a good chance of being on par with the two wheel drive model and the MPG figure will likely only be marginally worse.
This is partially due to the fact that the traditional ALL4 weight penalty has gone down to only 134 lbs with this new revised version. Furthermore, measures for reducing system-related losses and an energy-efficient operating strategy have made MPG loss much less of an issue. But enough of the high level. Let’s talk details.
The system is major revision to the one that debuted on the R60 Countryman. Power from the front drive to the rear axle is transferred by means of an angular gear (Power Take-Off) on the front differential and a two-part cardan shaft. The central component of the four-wheel drive system is an electro-hydraulically controlled multiple-disk clutch (Hang-On) inside the rear axle drive, which facilitates infinitely variable distribution of torque to the front and rear wheels. The corresponding commands are provided by an electronic control unit which, like the hydraulic pump, is located on the rear axle. The idea is completely invisible engagement resulting in constant traction in any condition.
The angular gear is mounted behind the engine on the automatic transmission and crankcase. The input shaft is a hollow shaft construction and directly connected to the front axle differential. In this way, part of the drive force is transferred from the differential basket to the cardan shaft via the hollow shaft, the crown wheel and the pinion shaft. The angular gear operates at a fixed gear ratio (1:1.74) and is permanently engaged, meaning that the cardan shaft always rotates when the vehicle is driven. Reversal of transmission takes place in the rear axle drive so that the front and rear axle drive shafts both rotate at exactly the same speed.
The multiple-disk clutch located in the rear axle drive (Hang-On) directs a proportion of torque to the rear wheels according to each driving situation, ensuring optimal power distribution between the front and rear. In extreme cases (e.g. the front wheels are standing on ice), the ratio can be 0:100. The required operating pressure (0 to 40 bar) is delivered by an electro-hydraulic pump, the speed of which is defined by a pulse-width-modulated signal from the electronic control unit. Pressure is not measured by a sensor, but extremely accurately by means of voltage and power alignment. In order to ensure maximum positioning accuracy, run-in behaviour and temperature influences are independently compensated, the system constantly adapting to ever changing operating conditions. We told you this is an improvement.
As before, when extra traction isn’t required the ALL4 system reverts to front wheel drive improving efficiency. That means the pump is deactivated, rendering the system unpressurised. In order to make use of additional saving potentials, the system has a multiple-disk clutch with a spring-loaded Efficient valve, which lowers the oil level in the clutch and significantly reduces friction losses (oil splash losses). When required, the system takes only fractions of a second to build up maximum operating pressure in the Efficient mode and thus deliver maximum torque to the rear wheels. As you’d expect this all happens without loss in traction or any discernible change in the drivetrain.
Like all MINI and BMW all wheel drive systems, everything is managed from the control unit of the Dynamic Stability Control feature (DSC). DSC analyses a large amount of data providing information in an effort to ensure optimum distribution of drive torque. This information includes vehicle speed, lateral and longitudinal acceleration, steering angle, wheel speed, longitudinal inclination, accelerator position and the setup via Driving Experience Control. Any adjustments are made within fractions of a second in an effort to make power distribution between the two axles virtually unnoticed by the driver. In addition to this, torque distribution is precisely regulated as to avoid any loss of power due to wheel spin.
Due to the DSC controlling everything, wheel slip can be detected at an early stage. In an example where a Clubman threatens to drift outwards over the front wheels (understeer), increased tractive force is supplied to the rear axle, allowing the vehicle to turn in more accurately. On the other hand, ALL4 directs excess force to the front wheels, should the rear of the vehicle threaten to swerve outwards. As a result, maximum four-wheel performance is available even before slippage occurs. Put simply, the updated system not only ensures best possible traction and safety in wet or snowy road conditions, but also enhances vehicle stability, cornering dynamics and ride comfort. Further, in driving situations where the interconnection of all four wheels is disadvantageous – i.e. in an emergency stop – the system opens the multiple-disk clutch completely within milliseconds.
Only if optimum power distribution to the front and rear axle is not sufficient to keep the Active Tourer on the desired course, DSC intervenes by reducing engine output and/or by decelerating individual wheels. Moreover, DSC assumes the function of a transverse differential lock: If a wheel spins without transferring power, it is automatically slowed down, whereby the axle differential directs more power to the wheel opposite.
Look for the ALL4 Clubman to hit US dealers this month.
Official release: The very latest MINI feeling in a whole new dimension – now also available with all-wheel drive; new MINI Clubman ALL4 combines the innovative vehicle concept in the premium compact segment with an even sportier and more versatile version of hallmark brand driving fun; newly developed all-wheel drive system for the latest MINI generation available in two engine variants.
Premiere for the new generation of the all-wheel drive system ALL4 with electrohydraulic regulation, optimised weight and increased efficiency in the largest and most versatile MINI model; ideal alternative and supplement to the characteristic MINI front-wheel drive featuring a new construction principle with power take-off bevel gear on the front axle, dual-section propeller shaft for power transmission and Hang-On multidisc clutch in the rear axle differential; distribution of drive torque between the front and rear wheels precisely adapted to the given situation due to interconnection of the ALL4 control unit with Dynamic Stability Control (DSC); swift response to changes in driving style and road surface enables extremely sporty handling and supreme traction properties in all weathers and road conditions.
Market launch of the new MINI Clubman ALL4 (combined fuel consumption: 6.9 – 4.8 l/100 km; CO2 emissions combined: 159 – 126 g/km) featuring highly powerful engines of the latest generation with MINI TwinPower Turbo Technology and also the current versions of the manual and Steptronic transmission; MINI Cooper S Clubman ALL4 with 2.0-litre 4-cylinder petrol engine (141 kW/192 hp) and standard 6-speed manual transmission as well as optional 8-speed Steptronic transmission; MINI Cooper SD Clubman ALL4 with 2.0-litre 4-cylinder diesel engine (140 kW/190 hp) and 8-speed Steptronic transmission as standard.
Intensive driving fun due to powerful engines and traction-optimised power transmission to all four wheels; optionally available: 8-speed Steptronic sports transmission with shift paddles at the steering wheel and Launch Control function for highly dynamic acceleration from standing; optimised fuel consumption and emission figures due to efficient design and functioning of the new all-wheel drive system ALL4 as well as extensive MINIMALISM technology; auto start/stop function as standard; GREEN mode including coasting with decoupled drivetrain in conjunction with optional MINI Driving Modes and Steptronic transmission.
All-wheel drive system ALL4 as an additional contribution to the highest level of everyday practicality and long-distance suitability ever achieved by a MINI; new MINI Clubman ALL4 combines hallmark brand go-kart feeling with secure handling properties and supreme driving comfort at all times; high-quality suspension technology unique within the competitive field featuring single-joint strut front axle and multilink rear axle: maximum agility due to large track width and weight-optimised, torsionally stiff body construction; electromechanical power steering with Servotronic function as standard.
MINI Clubman ALL4 as standard with Dynamic Stability Control (DSC) including Dynamic Traction Control (DTC), Electronic Differential Lock Control (EDLC) and Performance Control; sports suspension and Dynamic Damper Control optionally available; standard trim with light alloy wheels in 17-inch format; light alloy wheels optionally available up to a size of 19 inches.
New MINI Clubman now available in eight engine variants; extended variety for a vehicle concept that is unique in the compact segment in the tradition of the classic shooting brake; distinctive body design with dynamically stretched silhouette, powerful shoulder contour, long roof line and sloping rear; optimised aerodynamic properties due to Air Curtains in the form of air inlets in the front apron and air outlets behind the front wheel arches known as Air Breathers; high level of versatility due to the four side doors and characteristic, side-opening split doors at the rear; five fully-fledged seats; luggage compartment volume: 360 litres; rear backrest with optional 40 : 20 : 40 folding split; maximum storage volume: 1 250 litres; range of body paint finishes expanded to include Digital Blue metallic.
Distinctively designed interior with wide dashboard and cockpit facia frame in upper section; instrument panel on the steering column; central instrument with diverse display functions; intuitively operated air conditioning control unit; central console with electric parking brake, storage compartments, two cupholders, MINI Controller and armrest.
Weight-optimised and crash-optimised body structure; standard safety fittings include front and side airbags, side curtain airbags, 3-point automatic belts on all seats, at front with belt tensioners and adaptive belt force limiters, ISOFIX child seat mounting at rear and optionally also on the front passenger seat; tyre pressure display; excellent acoustic and vibrational comfort.
Full range of optional equipment to increase driving fun, comfort and individuality also available for the new MINI Clubman ALL4; MINI Driving Modes for individual vehicle set-up; modern driver assistance systems including MINI Head-Up-Display, Parking Assistant, rear view camera and Driving Assistant; LED headlamps; LED fog lights; electrically adjustable seats for driver and front passenger; Comfort Access including non-contact opening of the split doors; trailer tow hitch; panorama glass roof; MINI Excitement Package with LED interior and ambient lighting and projection of the MINI logo from the exterior mirror on the driver’s side when opening and closing the car; MINI Yours Interior Styles with backlit door bezels; alarm system including red LED status light in the fin antenna; range also includes: exclusive John Cooper Works and MINI Yours options and the current MINI Connected in-car infotainment program.