"The speed limit was repealed in 1995 when crude oil dipped to $17 a barrel and gasoline cost $1.10 a gallon ... this Fourth of July weekend, gasoline averaged $4.10 a gallon nationwide, with oil hovering around $145 a barrel. " - Wow, that puts it in perspective. - Gary Bacon II

I read an article before which said at $4/gallon, every 5 MPH over 60 MPH essentially adds 20 cents to the price of gas. - Scott Watermasysk

Funny thread comment re: the constitution in there. I can hear Jimmy Carter's energy crisis speech now..."by 1981 this nation will be free of it's dependence on foreign oil..." Er, I think not. - BISQ

In the words of Sammy Haggar, "I can't drive 55." - alanoakes

Is 55 some magic number? None of the changes in engine technology or whatever in the past 30 years affects that point of efficiency? Just curious and a little surprised. - felix

55 is actually a magic number, felix. Actually 60mph. In wind tunnel tests, most cars' fuel efficiency drops off severely over 60mph. - Phil G

The national speed limit was repealed in 1995 because the US House was controlled by Republicans for the first time since 1954. http://en.wikipedia.org/wiki... - Christian Burns

Just from watching the consumption screen, the Prius gets the best mileage between 55 & 60. - Mike Hussein Cohen