My own personal opinion about premium vs. regular is this. I had a 84 Suburban w/a 350/700r4 in it & it pinged like crazy burning premium, so I went to 87 octane & by the time I ran 3-4 tanks through it the pinging stopped. Even pulling a 16ft fully loaded trailer I would use nothing but 87 octane. BUT I will say this not all fuels are made the same. Some I got almost no mileage out of them (6-8mpg) others I got 10-13mpg out of them. Not really a lot better BUT it beats 6mpg...Joe