Description

Viscous Coupling – the temperature-controlled fan drive that turns the engine cooling fan on the 2.5 litre 300 TDi diesel.

The coupling sits between the water pump pulley and the cooling fan. A temperature-sensitive silicone fluid inside the unit increases its grip as under-bonnet temperature rises, driving the fan harder when cooling demand is high and letting it slip when demand is low – reducing parasitic drag, fuel consumption and fan noise.