NEWS FLASH..
Diesels have their maintenance problems too.
In 55k miles, my 8.3 Cummins ISC has had all 6 injectors pulled cleaned flow checked then reinstalled with new seals.. $2800 and change, #4 injector line replaced. $220 (yeah it broke) valve cover re-sealed, $110 and the exhaust manifold replaced. $829. All coolant hoses replaced, (now life time teflon type) the oil changed 4 times with the $70 filter, and 24 Qts of oil.
If you are going to run them, you must maintain them, and diesel parts are not cheap.
And to top it off, when they are installed in a coach, you can't get to anything.