Chuckanut
Give me a museum and I'll fill it. (Picasso) Give me a forum ...
To others.... do not just think of miles when it comes to timing belts.... there is also a time component...
An interesting comment and it makes a point about the differences betweeen consumer automobiles and things like aircraft, trucks, ships, etc. My understanding is that the later are usually maintained on a time basis. Change the oil after 400 hours of operation. Replace the frammit every 700 hours. Never let the gridget go past 140 hours without lubrication.
I have always thought that time makes more sense since it more realistically reflects what is going on. I can drive two cars 15,000 miles a year - one on highways at speeds near a constant 60 mph, and the other in stop and go city traffic. Obviously, the first car operates for a far shorter time than the second and experiences much less wear and tear overall.
Of course, modern automobiles require very little maintenance compared to the ones of 20+ years ago so this is possibly is academic.
Maybe the engineers in the group can comment on this.