gear and tire question
 

Its been awhile since i have been on here. I have 35 inch tires and a 3 in bl. I have a set of 4.56 yukon gears ready to install. I have been considering stepping down to a 34 inch tire and 4.11 gears though in hopes of better gas mileage. Anyone running this set up? I currently have 3.55 gears and my truck has no power and gets terrible gas mileage. Also what is everyone getting for gas mileage with 4.56 gears and 35's. Maybe i should just install the 4.56 gears since i already have them. Thanks for the help