In today's marketplace, steel and aluminum are the most common wheel
materials. Steel wheels are made in two pieces. The inner piece, which is called
the center, bolts on to the car. The outer piece is known as a barrel and receives
the tire. The two pieces are welded together to form the wheel. Most original
equipment wheels are made this way. Many aftermarket wheels are created this way
as well, especially ones made for trucks. Steel is durable and easy to repair. For
these reasons, it has remained a popular material for wheel manufacturing. The
other material, aluminum, is by far the most popular type of wheel we sell. Its
light weight, superior heat dissipation, and seemingly endless design variations
make it the material of choice for most buyers. Aluminum wheels can be
manufactured in many ways, and each method offers advantages.
One-piece cast wheels
Pouring molten aluminum into a mold creates a cast wheel. The metal then takes
the mold's shape as it cools and hardens. There are three types of casting
methods: low pressure/gravity, counter pressure, and high counter pressure
molding (HCM). Each method has its place in today's market. A wheel
manufacturer will select a particular method according to the weight, strength,
and finish that they have specified for that design. Naturally, the more
sophisticated and costly methods produce lighter and stronger wheels but at a
Forged / Billet wheels
The two words "forged" and "billet" have become synonymous. However, the
manufacturing process is called forging, while the material used is a billet.
Billet is the term used for a solid piece of dense aluminum. The forge, a huge
machine that exerts thousands of pounds of pressure on the metal, basically
presses or rolls the billet into its fundamental form. This forging is then
machined to a final finish. This process allows wheels to be built with much
less material. This results in lighter weight and unique designs, because the
process creates a much stronger wheel than other methods.
The processes mentioned above can be combined to produce a wheel of a
particular strength and weight at a particular price. For example, some wheels
have a cast aluminum center, welded to a steel outer, or barrel. Another type
of two-piece construction features a billet center welded to a rolled outer
(extruded aluminum rolled into a hoop). Still other wheels feature a split
outer so that widths and offsets can be made to custom specifications. This
last method is the three-piece type construction. In this type of wheel, the
center can be cast, billet or forged, and is usually attached to the outer
assembly by special screws or rivets.
This term is used to refer to the physical specifications of the wheel
and the availability of the sizes that will fit a vehicle. So, the fitment
specifications for a particular wheel and vehicle include the bolt pattern, the
offset, the wheel width and the wheel diameter. If you want a particular wheel for
your car, select our Find Wheel Sizes for My Vehicle section and it will guide you
to the styles available and the sizes that fit.
FWD stands for Front Wheel Drive and RWD stands for Rear Wheel Drive. Most
wheel catalogs use these acronyms to sort out the wheels available for these two
different types of vehicles. The great majority of the time, a FWD wheel will not
fit a RWD vehicle and vice versa.
First and foremost, wheels are purchased for styling the vehicle. You've
got to like how they look. Second, decide on the build method and quality. The
discussion of manufacturing methods above was intended to inform you of the different
ways wheels are made. Choose the manufacturing method you want at the price you are
happy with. Finish quality is important, so demand a nicely finished wheel. Finally,
decide on the price. We realize there are many tradeoffs between the various features
and price and that's why we carry a wide selection of wheels for every budget.
Finish refers to the type of surface treatment a wheel is given. Machined
or polished finishes are popular on aluminum wheels. "Machined" is what the wheel
looks like after the last shaping procedure (usually a lathe cut) has been completed.
An additional step involves passing the wheel through successively finer automated
and hand polishing processes. This results in the polished finish. A chrome finish
is also available on aluminum wheels, but requires three additional layers of metal
treatment (copper, nickel and chrome) to be achieved. Chrome finishing can
significantly increase the price of the aluminum wheel. That's where steel wheels
have an advantage: chrome goes on in one simple, inexpensive step. Finally, paint
goes on everything and can be applied in single or multiple color schemes. Often the
powder coating process is used to apply paint, resulting in a heavy, durable finish.
In today's market, wheel manufacturers combine finish methods in different ways. For
example, the popular tuner type designs often feature a silver center and a machined
or polished lip. The last step in many styles is to seal the wheel with a clear coat,
making the wheel much easier to maintain.
In most cases, using a spacer (of greater than 3mm thickness) or an adapter
means you will be using a wheel that was not designed to fit your vehicle. Unless you
get the advice of a professional, this can cause trouble. An incorrectly fit wheel
almost always leads to excessive wear on suspension parts, poor ride and potential
mechanical failure. In the vast majority of applications, we do not recommend the use
of these devices.
Most aftermarket wheels are manufactured with a center hole that will fit
a wide range of vehicles. The hub-centric ring is used to fill any gap that may
exist between this hole and the vehicle's hub, thus centering the wheel on the axle.
If you have vibrations after installing new wheels, chances are hub-centric rings
were not used.
Probably the single biggest mistake when cleaning wheels is to use super
cleaners, which can contain harsh abrasives. Mild soap and warm water is sufficient
for routine cleaning. After cleaning chrome-plated wheels, you can apply a non-abrasive
wax or cream to prevent surface corrosion. If you have clear coated wheels, skip this
step. Don't let tire cleaners come into contact with your wheels, and try not to spray
cold water on hot wheels. If you go to the car wash, don't let them use steam cleaners
or strong chemicals on your wheels. To brighten up your polished wheels (that don't
have a clear coat), use a polishing cleaner provided by the manufacturer. To maintain
this great look, apply some wax to keep the weather out.
That's a job that's best left to your tire dealer. A combination of special
tools and methods are used to install wheels so they deliver the performance you paid
for. Initial mounting of the assembly on the vehicle requires positioning and starting
the lugs by hand. Next, the lugs can be pre-tightened using a hand wrench or torque
stick (a tool that ensures a lug is not over tightened). The final torque setting is
applied using a calibrated torque wrench. It sounds complicated, but a trained technician
(like those at Discount Tire)
can get this done very quickly.
If you have a vibration or pulling symptom, chances are you may
have damaged the wheel. Again, go to the tire dealer and let him inspect your wheels. He
will place each assembly on the balancing machine and check for run-out (a hop or wobble).
If you have a damaged wheel, get the unit repaired or replaced immediately to avoid