I purchase my filters from Peterbuilt of Lafayette, a local truck center, they carry a complete stock of Fleetguard filters for my Cummins ISL400. The oil filter is $36.45, the fuel seperator is $31.07 and the fuel filter is $12.94. I pick up everything locally so there is no shipping and handling. The oil I get from WAl-Mart, DELO 400LE 15W40 around $11.34 per gallon, I use 7 gallons, engine and filter. Check around at the local truck dealers for your filters, they usually carry a plentiful supply of filters and you may not have to pay shipping and handling. Just a thought!