Automatic gearboxes use a 'fluid drive' - effectively it is the viscosity of the gearbox fluid which transfers the engine output to drive the car and unlike the direct gear drive of a manual gearbox, involves a degree of slip which the car manufacturer caters for with the modest liquid to liquid heat exchange looped through the radiator. However few manufacturers have specifically catered for caravan tow duty on their automatic gearbox models. Fords Mondeo, Granada automatic models after 1995 feature an oil to air secondary cooler as standard, like the kenlowe auto transmission cooler, providing tangible evidence from a major car manufacturer that automatics used for caravan towing need significantly more cooling than the modest pipe looped through the hot radiator tank! The Kenlowe automatic transmission 'auxiliary' cooler provides up to 50 times more cooling than the standard provision - real protection and peace of mind for when you are towing on holiday!

With most caravans, weighing the equivalent of 10 rugby players, it is easy to understand how you can overload your car and therefore the gearbox. As a result with a caravan in addition to your family and holiday luggage, it is no wonder that your fluid drive automatic gearbox suffers serious slippage when pulling uphill or pulling away in stop start traffic! Slippage causes heat, heat causes the oil to become thin, thin oil causes more slippage which causes more heat etc. etc. until the oil pressure builds up damaging the seals and the brake bands in the torque converter. In some instances over hot oil expands, syphoning out of the gearbox breather, where it atomises in the slip stream under the car before coming into contact with the hot exhaust causing a hot oil smell and wisps of smoke!

Effective auto gearbox cooling avoids expensive specialist transmission failure repair and a lost holiday!