Transmission oil coolers

Automatic gearboxes

In road usage the main problems experienced are when vehicles are used for towing or where engine modifications are causing more power to be fed through the gearbox.
Many vehicles have some form of oil cooling but this is usually inadequate for extra loads, in these cases extra cooling is desirable because even if actual breakdown does not occur, higher temperatures shorten the life of seals which can be as expensive to replace as an entire gearbox.
The oil in most modern automatic transmissions is cooled by a heat exchanger tube in the water radiator, a secondary Mocal cooler may be connected in series by interrupting this flow, cutting one of the oil pipes leading to the water radiator and securing hoses to the severed ends using hose menders.
Where water overheating is also a problem in arduous conditions or where the primary cooler in the water radiator is leaking it may be bypassed by connecting directly to the Mocal cooler by cutting both hoses.
Old Borg Warner gearboxes are provided with means of tapping the oil flow either by a loop pipe or two plugs on the right hand side of the gear box just above the sump. Renault gearboxes have two plugs adjacent to the left hand drive shaft. Only ZF boxes that have an existing cooler can have additional cooling.

We can supply an automatic transmission oil cooler kits designed to fit an oil cooler behind the front grille usually in front of the water radiator, brackets are provided to enable the use of the water radiator mounting bolts to secure the cooler. Kits come complete with a cooler, textile braided hose plus all the necessary clamps, nuts, bolts etc.

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