Toe in alignment decreases mileage (mpg)
 

Big Oil loves the toe in alignment found on some vehicles. This is also where gas mileage can be improved since a vehicle with too much toe will be creating excessive friction and using up fuel (and tires) faster than it should via these links: http://www.edmunds.com/ownership/tec...8/article.html
http://www.ehow.com/how-does_4603118...t-vehicle.html