so i have a 03 frontier crew cab with the supercharger with around 57000 miles, i have owned it for almost a year and have not been able to touch 300 miles on a tank of gas. im not sure if your supposed to reach that or not but i am only getting on average around 250 miles on a tank, and most recently i took a road trip all highway and barely got like 11 miles to the gallon which i think is not right. how do i get less miles on the highway as opposed to the city. anybody have any comments or suggestions on what i should do or what could be causing the problem, i will be thankful for anything i can get-thanks

 

i have a 96 4x4nissan truck with a 2.4 liter 4cyl. ,what can i do to get better gas milage and more power. also does that tornado fuel saver really work.