An easy way of turning a conventional, front-wheel-drive vehicle into a hybrid is to power the rear wheels with an electric motor. GNK has developed a clever rear-axle system that can t in in the space envelope of the rear suspension. The co-axle design is compact and, claims GNK, results in excellent noise, vibration and harshness characteristics. The unit also has a clutch that can decouple the electric motor when not needed. This will both reduce frictional losses and prevent electric motor over-speed during highway use. When connected, the electric drive not only ful ls a hybrid role, but also endows the vehicle with all-wheel-drive capability. This is used in the current Volvo XC90 and XC60 T8 hybrid applications.