Owners manual says every 15,000 miles for my 2015 CTD longhorn DRW. I had it changed at 7500 miles though since I towed my TT after I bought new. Going to change oil every 7500 miles. Fuel filters you can change. The rear under the frame filter is a big pain IMHO. I used to change the oil and fuel filter in my previous 2006 CTD all the time. Not as easy to do now with newer trucks. The fuel filters for newer Rams are not cheap anymore and dealer or any shop will charge around 360.00 bucks for both.