Boy 800k and K/n filter that should start the air filter wars. my truck now has 446770kms. been using rotella 15-40 since new,doesnt use any oil between changes every 6000k. and yes I to have had a k/n filter since new. still have the original vp-44. I use mmo and howes meaner in every tank,dont use it in the oil. I have been an aircraft engineer with USA A&P for 25 years. on any engine you crank up the H. P. ,increase the heat, Rpms etc you will get more wear. Manufacturers know this that why the time between overhauls are shorter on engines that are higher H. P. ,run hotter etc. Changing filters ,and oil ,keeping the fuel clean ,dont add power increases that will raise temperatures I believe will give you the best chance of long engine life. my 2 cts. have a good day ,and long life to your Cummins .