I have my radiator and other cooling units out for service. Thinking that I will repair, clean and restore all before they fail on a trip. Question is this, Should I replace my Hydraulic fan drive motor at this time as a proactive effort? It is not leaking and works as it should. Coach is a 2004 Signature with Detroit Series 60. 85K miles. We are replacing all hydraulic hoses, cooling hoses and pipes and a two year old exhaust system that is rusted through. ugh. It is a Saur Danfoss that was built in January 2004 according to its tag.