went to the dealer today to see why my highway mpg is only 21 no matter how hard i try. he askes me what brand of gas that i use? i said that i usually use "cashions" down the street. he said to try BP and that my mpg would go up 3-4 mpg highway. i am pretty sceptical, but he swore by it. he worked for them for years and said the quality in brands is very different. i have always read they were all identical, but i will give it a try. 21 mpg going 70mph in 6th gear should equate to at least 25 or better.