THE Forester employs different four-wheel drive systems depending on whether the vehicle is fitted with a manual or automatic transmission. Manual transmission models use a viscous coupling limited slip centre differential to transmit the engine power to all four wheels - it operates for the most part (with a static weight distribution) with a torque split front to rear of 60/40. Automatic transmission models use an active torque split system to drive all four wheels - a computer constantly monitors the driving conditions and distributes torque accordingly. This system has an operating torque distribution range from 95 per cent front/5 per cent rear to 50/50, but operates with a 60/40 front to rear ratio under normal conditions.