I just had 285/70/17's installed on my 2x4 screw with a 4.6 and 3:55 gears , anyone know how much the tires will affect my gas milage? will it make it alot worse, or mabey just 1mpg or so ?any one else with a similar setup have their mpg handy? THANKS!

 

The difference in size is going to make it seem worst that what it actually is, you need to have the speedo re calibrated to adjust for the new size to get a more accurate measurement. I put the same size on my truck and noticed about a 1 to 2 mile reduction with my speedo re calibrated.

 

how much is it to have the computer recalculated , like a ballpark figure?Thanks!

 

Most dealers charge around $80.