First thing if you want to be truly informed join the Turbo Diesel Register "TDR". They are the original RAM/Cummins group. They are not a bunch of guys that mod their engines and then complain about it like some other forums. You will get advice from people that are actually in the industry along with some very seasoned RAM/Cummins guys.
Stick with Mopar or Fleetguard filters. Mopar/Raycor for the frame mounted pre filter. Fleetguard makes the Mopar filters. If there is a filtration warranty issue RAM can deny warranty, DON'T use lesser quality filters!!!!! Amazon has great pricing on all of the filters. Genos Garage is a good place to buy RAM/Cummins parts they are part of the TDR.
Change oil when the computer tells you with a HIGH quality full synthetic 15-40 oil unless you live at the North Pole! I use AMZ/OIL 15-40 full synthetic. At 10K on my oil the computer says 33 percent life left, that is right on for a 15K change.
No fuel conditioner is required.
These Cummins engines are very easy to keep happy!
Change fuel filters when the truck tells you to, up to 15K. Change the air filter at 15K.