Misconceptions on wheel alignment

Example of a frame crack on a factory lift frame trailer.
Photo Credit: Picasa

by Don Stec

Driving on rough terrain as outdoor enthusiasts often do, can play havoc with your vehicle. This column has to do with common misconceptions the general public has about the frequent problems of alignment.

Complaint:  I have had my car aligned three times at three different shops and it just keeps slipping out of alignment.

Alignments do not slip out unless a bolt or steering component is loose. Vehicle owners often imply a mistake was made because the alignment technicians neglected to tighten something adequately.  However it would be highly unlikely that 3 technicians would make the same mistake.

What I have found most often is, wheel alignment is set as a front wheel to wheel comparison, not to the centerline of the vehicle or the thrust line of the rear axle. New or rotated tires develop the same unusual wear pattern, giving the car owner the impression the alignment has slipped out.

I have discovered that many of these vehicles have frame alignment or steering linkage problems.  Some problems were so minor they could not be detected by the naked eye. The alignment technician did the best he could, but he could not achieve “Total Vehicle Alignment,” due to the condition of the vehicle or limitations of shop equipment. This is one of the major reasons I decided to buy my own equipment and do total vehicle wheel alignments.

Coachmaster has been doing frame repairs on vehicles for over forty seven years and it only made sense to do our own wheel alignments.  This is not very common in body shops today and was very uncommon forty seven years ago.

Complaint:  No one can align my car: it has a constant pull.

After vehicle owners tell me they have had multiple alignments and the car still pulls, I look for the unusual, starting with air pressure and different brands of tires.  Just because tires have the same number on the sidewall does not guarantee they are the same diameter if they are different brands.  I use a large caliper gauge to check the diameter of each tire. I have found tires with the same numbers on the sidewall differ in diameter by as much as ½ inch.  

Even if the wheel alignment specifications are perfect the total vehicle geometry will not be if the tires do not match!  A pull or unusual tire wear can occur. I continue to be surprised on how few people know this.

Complaint:  My tires wear funny but my car does not need a wheel alignment because I have never hit anything.  

If your tires are wearing funny you have a tire, frame or wheel alignment problem!

During the life span of a tire and many thousands of miles traveled, the tires may have turned a million times.  The roads today are in desperate need of repair and it would seem unlikely that a driver would never hit a chuckhole or a hole on the shoulder during the life of a tire.  Normal wear of steering components and a defective tire are also possible causes to be considered.

Complaint:  The tires on my trailer wear uneven.  Isn’t that just the nature of trailer tires?

Many trailer owners seem to accept this as a fact.  Some have told me they just buy new tires every year or two. A major problem with trailer wheel alignment is the trailer ran off the roadway hitting the curb or chuck holes on the shoulder.  A wider turn is necessary when towing, especially when the trailers are very long as travel trailers often are.

A new problem has started to show up.  Some travel trailers are being built with the body raised much higher to provide more ground clearance.  After a few years of use we have discovered frame fractures and complete breakage of the frame.

This is caused by the additional stress to the frame by lifting the body higher.  I only know of one manufacturer that has provided a reinforcement kit. We have successfully built our own reinforcements for many trailers.

Coachmaster Collision repair* is a past recipient of the District Attorneys award for honesty and integrity in business.

Don Stec is the founder of Coachmaster, a full service collision repair facility also specializing in the collision repair of RV’s. Now retired, Don is proud to have sold the business to long time manager Allan Gordon. Call Coachmaster at 530-243-1310, or stop by at 6851 Eastside Road. Redding, CA.