How many hours before you change your oil on a diesel engine?
wow.....is this a trick question ????
is this a new machine? or new to you? IF new - what hours on the ol' girl?
IF new to you - how many hours on her?
rule of thumb - new - first at 50 then at 200, then again - some change engine oil every year, even under 50 hours.....
if used - then change it every year or every couple hundred hours.
diesel engines place a lot more demands on an oil than gassers do, and should be "watched" over a little closer!