mobil 1 went to this formula cuz the manufacturers have changed
their requiremets. mb has changed to a 13,000/ 1 year requirement.
i'm a true fan of mobil 1 now. just seen to much posative stuff
from it. a 7,500/six month interval is about right. for those that truly
do your own maintenance then a one year interval is fine. i give my
customers the best i can cuz thats what they expect. city driving is considered hard use so if you use dino then you would have to change
it more than has been done. i have had two customers that cooked their
140's till their was no oil pressure. but they had the mobil 1 i installed.
a few oil changes and they are still on the road with no ill effects.
do that on dino. its just the cheapest damn thing you can do to the most
important thing in your car you can do.

george