Are you ready for a little trivia today?  When was the first rim used on a vehicle?  If you guessed 1 B.C. then you would be correct.  The first rims were used to protect the wooden wheel of chariots in Ancient Rome.

Not so ancient now, the rim is the outer edge of a wheel, the part that holds the tire.  Many people use the terms “wheel” and “rim” synonymously but they are, in fact, distinct parts of a car.

A standard automotive steel wheel rim is made from a rectangular sheet of metal.  The metal plate is bento to produce a sleeve with two free edges welded together.  In today’s world, one-piece rim and wheel assemblies are made by casting or forging.

The characteristics of a wheel rim are as follows:

  • Diameter:  the distance between the bead seats, as measured in the plane of the rim and through the axis of the hub.
  • Width:  separation distance between opposed rim flanges.
  • Type: depend on the type of vehicle and tire.  Most passenger vehicles use one-piece rims with a safety rim profile.  Big heavy duty trucks use a removable multi-piece rim assembly.
  • Vehicle performance:  since the rim is what attaches to the wheel, it obviously will affect the performance of your vehicle.  Overly wide rims may cause more vibration and less comfort, while overly narrow rims could affect handling, especially on fast cornering.

There is variation of course, but the general rule is that the rim must be within certain parameters to ensure a safe and comfortable ride. Very wide tires on a narrow rim can overstress the rim and damage the tire, whereas very narrow tires on wide rims will give a hard ride and can result in the tire blowing off.  That is definitely not what you want to happen.

Having said all that, what is a buyer supposed to do when shopping for rims?

The average buyer shopping for rims should have no trouble.  As stated earlier, most rims are attached to the wheel, so when you are shopping for used wheels just stick with the manufacturer suggested wheel sizes.  It would be rare that the average driver would ever have to purchase a rim that is separate from the wheel.

When shopping for wheels and/or rims, always check out your local salvage yard for the best deals in town. There you will find quality used parts for great discounts.