Fifth-generation Haldex coupling. Permanent 4MOTION all-wheel drive has always been a trait of the Golf R. The latest generation 4MOTION system is now being used in the fourth-generation Golf R. This all-wheel drive system is coupled with a 6-speed gearbox that has a reinforced clutch and short-travel shifting. Another optional feature is automatic shifting with a 6-speed dual-clutch gearbox (DSG) that also offers manual shifting as an alternative.
The 4MOTION all-wheel drive system of the Golf R, further perfected by enhancements such as the Haldex 5 coupling, is activated even before any wheel starts to slip. This eliminates nearly all traction losses. The system achieves this by using an advanced control function based on specific driving conditions. When operating under a relatively low load or when coasting, forward propulsion comes primarily from the front axle, and the rear axle is decoupled. This basic drive layout saves fuel. However, the rear axle of the Golf R can be variably engaged in fractions of a second whenever necessary. This is done via a Haldex coupling, which is activated by an electro-hydraulic oil pump.
Situation-based power distribution. A control unit continually calculates the ideal drive torque for the rear axle and controls how much the multi-plate clutch should be closed by activating the oil pump. The oil pressure increases the contact pressure at the clutch plates in proportion to the torque desired at the rear axle. So, the amount of pressure applied to the clutch plates can be used to vary continuously the magnitude of the transmitted torque. The wheels of the 300 PS Golf R are prevented from spinning even when driving off and accelerating, because the control unit regulates the torque distribution as a function of dynamic axle loads. Activation of the Haldex 5 coupling is based primarily on the engine torque demanded by the driver. In parallel, a driving status identification system within the all-wheel drive control unit evaluates such parameters as wheel speeds and steering angle. If necessary, nearly 100 per cent of the drive torque can be directed to the rear axle.
Four-wheel EDS as transverse locks. In addition to the Haldex coupling that acts as a longitudinal lock, four electronic differential locks (EDS) integrated in the electronic stability control system act as transverse locks. The system briefly brakes a wheel that is slipping, enabling uninterrupted and stable transfer of drive power to the wheel on the opposite side. In the Golf R, the electronic differential locks are implemented at both axles in what is referred to as four-wheel EDS.
XDS+ makes tracking in bends more precise. In addition, the Golf R is equipped with XDS+ at the front and rear axles. This brakes the wheels on the inside of a bend during fast driving through bends, optimising steering behaviour. In the latest version, known as XDS+, this functionality is applied to a larger range of dynamic performance – making the vehicle more agile even when the car is not in an acceleration state. In technical terms, XDS+ is a functional extension of the electronic differential locks. When the car is being driven fast, as soon as the electronics detect excessively light loads on wheels on the inside of a bend, the hydraulics of Electronic Stability Control (ESC) apply brake pressure to this wheel to restore optimal traction. XDS+ thereby operates as a transverse differential lock that compensates for understeer during fast cornering.
ESC Sport. The new Golf R is equipped with the "ESC Sport" function as standard. The system is activated by a two-stage switch on the centre console. When the driver presses this switch briefly, Electronic Stability Control (ESC) switches to the "ESC Sport" mode. In very fast driving with lots of bends – such as on a race track – the ESC system reacts with a delay, which enables even more agile handling properties. When the ESC button is pressed for longer than three seconds, the system is fully deactivated for professional driving on a race track – this deactivation is only available in the Golf R and not in any other models of the Golf series.
Notes:
TDI, TSI and DSG are registered trademarks of Volkswagen AG or other companies of the Volkswagen Group in Germany and other countries.
All features and technical data apply to models offered in Germany. They may differ in other countries.
