As an aside here, Gaffney and Cummins will both allow you to provide filters and then you aint paying their price for them. They give military veteran discount as well. I usually buy my filters on Amazon, I carry two sets of genset fuel/oil/air with me. I could have sworn I had two oil filters for the main engine, but cannot find them now. Going to get two more. I should also carry extra fuel filters as well in case I get a load of bad fuel, but have not broken down and gotten them yet. Just actually got the tool box situation sorted out and put that in coach. Aint got a lot of storage in there. Based on the fellow who had the porpoise issue and found out batteries are bad, I charge mine up once a week unless we are using coach. I check levels in them once a month, and recently cleaned out that compartment and the tops of the batteries, so that job is done. Freightliner changed oil/filter in genset so that is done. If we don't go south before real cold weather, going to have to winterize coach, so should buy Rv antifreeze for that project. Next August, it's full service on Genset, and its also annual for coach, will make appointment in Gaffney, and let them do it all. Air Cleaner might be time then too, 2 years old and maybe 18K miles or so. Don't know interval, will have to check.