Tire Buying Basics - Choose the Right Tires
By Mike Bumbeck /autoMedia.com
While choosing the correct diameter of tire is an obvious choice, there is
almost an algebra book's collection of number and letter designations on the
sidewall of a modern tire. The biggest one is the most important and usually
goes something like P235/70R15 87H. Reading from left to right the translation
is this. The P stands for passenger. Easy. The 235 is the width of the tire in
millimeters. The 70 is somewhat tricky. This number is the tire's aspect
ratio, or percentage of the width that is the tire's height. A 70 series tire
is 70 percent of the tire's width tall. The higher this number, the taller the
tire, and vice versa. The R stands for Radial. Easy again. The 15 is the wheel
diameter the tire will fit. The far right number is the load rating, and the
final letter the speed rating. The higher each one of these is, the greater
load and speed the tire is manufactured to handle. There is another number
called the treadwear rating. This number gives an idea of how long the tire
will last, or how fast it will wear out—depending on how you look at it. Read
Grip Versus Wear
Tire wear is dependent on the blend of natural and synthetic rubbers from
which the tire itself is made. The recipes for these blends are what make the
tires perform in one way or another. A softer, sticky, performance blend will
help the vehicle hug the road, but won't bring long tire life along with it.
An all-season M+S tire will bring long tire life and a smooth ride, but not
the same blazing performance as a softer performance blend. Snow tires work
best in the snow. Soft and sticky high-performance summer tires work best in
the summer, and will turn hard as hockey pucks when the temperature drops.
Off-road tires are built with mud, rocks, and gravel in mind, and as such
don't play well on smooth pavement. The key point is that there is no single
do-it-all perfect tire that works without compromise. Tires are manufactured
to work best in a defined set of circumstances. Choosing the right tire rolls
in behind first determining what kind of driving you do, and taking time to
honestly examine your driving circumstances. That will go far in making the
right decision the first time around.
Five Tire Buying Tips
Your driving style and operating environment will determine the best tires for
your vehicle. Be honest with yourself and your dealer.
Tire performance is about compromise. High-performance tires wear quickly and
can be noisy. Quiet, long-wearing tires sacrifice some performance.
Consider a dedicated set of wheels for Snow Tires in winter climates. Always
run with a full set of four snow tires.
Don't mix and match types and ratings of tires. Handling and braking will
suffer. Always replace tires as a set.
Always use tires for their designed purpose. Off-road tires are useless on the
highway, as are high-performance summer tires in wintry conditions.