The increased mileage you get out of vehicles now is, in large part, due to the huge improvement in lubricants. Old Triumphs and Hardleys you used to need to freshen up the top end around 30,000 to 40,000 miles. Triumph had a really good bottom end though that would last through several top ends. If maintained of course. Cars around 100,000 miles was good now over 200,000 isn't unusual. I have seen 300,000+ and old Subarus (pushrod engines) would still be going strong at over 400,000, we used them for tool wagons in the junkyard. Rotted away but running strong.
