[qcj]

I realize that some of my questions are elementary. My Cat engine did not have a coolant filter and had ethylene glycol coolant and after 3 years I changed it to ELC. It was not a easy task flushing the system a number of times even with the thermostats removed. The Cat had two thermostats and recommended them to be replaced every three years (I don't know the recommended time for the Detroit). Steve you said filter change about 15,000 miles on both coolant and hydraulic. Do you change the filter without changing the coolant or hydraulic fluid? I would guess so. I have done a strip test on my coolant and it checked OK.

I realize John was talking about all filters. On top A/C are going to have more filters than those underneath, and some of us have more water filters than others. I only have one where I know others have several.
I guess my main concern was the coolant and hydraulic filters which I am not as familiar with. I have had my Newell a year now and it is coming time to start thinking about maintenance. Motor Homes of Texas serviced it completely before I bought it, so now it is my turn.
This Newell Forum has been a great asset for me to learn about these great machines. Thank You.