Wheel Balancing

Out-of-balancetires will cause a car to vibrate at certain speeds, usually between 50 and 70 mph. A tireis out of balance when one section of the tire is heavier than the others. One ounce ofimbalance on a front tire is enough to cause a noticeable vibration in the steering wheel at about 60mph. To balance a wheel, the technician will mount it on a balancing machine which spinsthe wheel to locate the heavier part. He will then compensate for the heavy part byattaching a lead weight on the opposite side. Many people are pleasantly surprised at howsmooth their car drives after balancing all four wheels.

Most high quality tires will hold their balance fairly well and go out of balance verygradually. If you notice a vibration that wasn't there the day before, it is possible thatone of the lead balancing weights fell off. If you feel the vibration mostly in thesteering wheel, the problem is most likely in a front wheel. If the vibration is mostly inthe seat, the problem is probably in the rear.

For those of you who are very sensitive about vibrations and your shop can't seem toget that last bit of vibration out, check to see if you have locking wheel lugs. Somelocking lugs are as much as 1.5 ounces heavier than the other lug nuts whichtranslates to about 1/2 ounce at the wheel rim. Try putting a 1/2 ounce weight oppositethe locking lug and see if it helps.