What's the deal with such a discrepency in the owners manual and dealerships? According to owner's manuel the oil is changed at 7,500 miles and fuel filter every 15,000 miles. Dealerships (I called two) said for oil/filter at 5,000 miles and fuel filter at 8,000-12,000 because "we don't have much luck trying to go 15,000 miles with the fuel filter". Millions of dollars on research and development on the engines to come up with manufacture recommendations only to have a service writer/tech say something otherwise. I realize that doing the service earlier than recommended is good insurance...but a couple to several thousand miles is something a little different.

 

If the dealer can only get the CJ rated oil ( For use in both 5.9's and 6.7's trucks) then the CJ is only designed to go 5,000 miles. Many are running it longer however. Also, $$$$$$$$$$$$$$$ the dealer will make more money off of you if you bring your truck in every 5,000 rather than 7500!!! Fuel filters are a must... I change mine at ever 5,000 mile oil change. 14 bucks and 5 minutes to do... You never know if your going to get some bad fuel etc..