Fluid Cooling

AUTOMATIC TRANSMISSION – ZF 5HP24

44-2-36 DESCRIPTION AND OPERATION

Fluid Cooling

1 Fluid feed
2 Fluid return
3 Fluid cooler

4 Engine coolant feed
5 Engine coolant return

The fluid cooler is located at the bottom right hand corner of the engine. The cooler is cooled by engine coolant which 
flows in a water jacket around cores within the cooler body. Transmission fluid enters the cooler and flows through 
the cores where it is cooled by the engine coolant. The fluid leaves the cooler and is passed back to the transmission. 
The transmission fluid is pumped through the cooler by the transmission fluid pump.

The fluid cooler has a thermostatic valve which is opened by transmission fluid temperature. The thermostatic valve 
is opened at a transmission fluid temperature of 80

°

C (176

°

F) and allows engine coolant to flow through the fluid 

cooler.

2

M44 1839

3

2

1

1

5

3

4