I am at 340,000+ miles on my 2000 International t444e - and going strong. It seems to be driving better now than when I picked it up over two years ago.
I have had a few parts replaced - but I change the oil / filter every 5,000 - 6,000 miles and the fuel filter when needed - I use fuel additives (diesel 911 - or Howe’s) regularly and that seems to keep engine strong.
I also talk to the engine a lot.