On Fri, 4 Apr 2008 11:49:03 -0700, "Capt. JG"
wrote:

I don't know about most, but my guess is that a substantial portion of
truckers are independents who likely do pay for maintenance. You're right
about the warm-up... the engines are already hot from long driving. I can't
recall if the driver ever shut the thing off in 3000 miles except to stop
for fuel or a bio stop.

We once had a post here from a guy who was responsible for diesel
maintenance on a fleet of trucks at a gold mine in northern Canada.
He said that basically the trucks idled all winter, over 3,000 engine
hours each. He said that by spring the engines were mostly junk if I
recall correctly.

In contrast, a heavy duty diesel in normal service, and with good
maintenance, will go 5,000 to 10,000 hours between overhauls.