at 70 miles to one hour of operation the service interval would be 42hrs=3000 miles to 64hrs= 4500 miles.
at 30 the service intervals would be 100hrs=3000 miles to 150hrs=4500 miles.
toyota uses 25 miles to one hour and that makes the service interval more realistic or at least at a level that doesn't scare the **** out of the customer.
i know as a toyota guy that my view is a little biased but i have seen some trucks that have been in 24 hour heavy service with over 30,000 hours and still going like that **** pink bunny. i am sure some other brands can do as well.