Typically: OM617,601,602,603 the O.T. is inside the Oil Filter Housing...

The OM606.XXX series I don't know the Location.

Someone will Chime In.

Major concerns are Robustness of the Cooler,Fittings AND the Hoses!

You Blow a fitting or a hose and the Engine is TOAST!

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'84 300SD sold
124.128