All parts of a wheel assembly are manufactured with tolerances for imperfections.By assembling together all these parts and their imperfections without balancing the complete wheel assembly, you are playing "Russian-Roulette" with your mechanical repairs, tire expenses and fuel economy.The vibration that the driver feels from the steering tires also applies to all of the remaining wheels of the vehicle.This up and down force (vibration), damages not only the tires, but over a period of time, is one of the main reasons that wheel fasteners, maxi booster clamps, U-bolts and torque rod bolts work themselves loose, not to mention cracking in frame rails and cross members, breaking of air brackets, door hinges, lights, etc.When this out of balance centrifugal force and its rebounding multiplying factor hit the road, it has the same effect as slightly applying the brake or hitting a pot hole hundreds of times per minute, increasing the rolling resistance of the entire vehicle, therefore decreasing fuel economy.

WHEEL POSITION CONTRIBUTIONS TO FUEL ECONOMY*