Misconceptions about Front End Alignment

I have recently and in the past heard people say they have a vibration and need to have the car’s front end aligned. Now if the alignment was so far off, say a bent part, this could be true. Vibration, shaking, or steering wheel wobble is caused by many things but not the alignment.

Causes for this would be one or a combination of the following: tires out of round, the balance of the tires, bent rims, warped rotors, a bad steering component, and/or a bad strut/shock. While working in a shop as an alignment tech for years, I saw all of these on a daily basis—most common problem being a bad tire and a tire out of balance. If a tire is perfectly round, in balance, with a tight front end, the car or truck should ride smoothly down the road. It still may drift or pull. (A pull is detected if while driving down a straight road and momentarily letting go of steering wheel, the vehicle drifts into the next lane by itself.)

Regardless of a bad shock or the alignment being off, the reason to have the front end aligned would be to correct tire wear problems, keep a vehicle from drifting or pulling, and increase fuel mileage (there’s less friction if the vehicle does not have to drag a tire just make it roll). We are only talking about small degrees of angle here, not 45 degrees.

There are a few important angles when measuring and adjusting a front end. The first being camber. This would be how far the upper portion of the tire is leaning, whether it is in/out or positive/negative. If this angle was off from specification, the vehicle may have a pull or uneven tire wear from inside to out. An incorrect reading may be caused by a bent suspension part, worn steering part, or vehicle sag on the springs due to age. The next angle to check would be caster. This angle does not wear tires. It would cause a pull. Basically this angle is a measurement of placement or degrees of separation between the upper and lower ball joint. If angles vary from driver to passenger side more than .5 degrees, the vehicle may pull. This would be caused from one tire being forced forward more than the other. The most important angle after the others have been set would be toe in or toe out. You've seen all these angles if you've seen a toy Matchbox car that has been stepped on. They just don't seem to roll well with a bent axle or tires pointing in opposite directions. Toe would be the direction the center of the tire is pointing on a centered basis of the vehicle. If this angle is off it will wear tires quickly. If it is far enough off, it can cause darting when the steering wheel is barely touched.

I trust this helps you understand what causes vibrations and tire wear. If you have a front end, tire, or alignment problem, we would be glad to take a look, explain further, or refer you to a trusted expert. Call WHEEL FIX IT Mobile Vehicle Maintenance and Repair at 615-496-2544 or contact us on our Web site http://www.wheelfixitmobile.com.