Country roads, take me home
To the place I belong...
John Denver's song may make you long for scenic byways, but
country roads can wreak havoc on your vehicle's tires.
Selecting the right tires for secondary and off-road
conditions will enhance the performance and safety of your
vehicle and optimize tire wear.
Tires generally fall into three categories: highway;
all-terrain or general-purpose; and off-road. Each category
is defined by tread pattern and the tread/tire compound (the
materials from which a tire is made). The rougher the road
surface the more aggressive the tread and the harder and
stronger the compounds. Off-road tires, for example, have a
deeper tread depth for greater traction in sand, mud and
snow.
Secondary roads have either asphalt or gravel surfaces.
Tires that provide good traction are especially important on gravel because "the limestone
aggregates create a lot of slipping and
sliding between the tire and the surface," notes Mark Hanna,
Iowa State University Extension ag engineer. "And a stronger
tread compound stands up better to the rough and sharp
surfaces that rip and tear (called chunking) tires."
For cars, minivans or SUVs driven on both paved and
secondary roads, a retailer will likely recommend a
general-purpose tire. It gives a smooth ride on hard
surfaces but provides needed traction on rougher roads,
notes Mark Cherveny, product manager for light-truck tires
at Goodyear. General-purpose tires also perform well in all
types of weather.
Light pickup trucks are usually equipped with these tires,
too, as they stand up to limited off-highway duties such as
driving over fields and pastures. However, depending on how
the truck is used, you may need to consider the
load-carrying capacity (load index) of the tire.
High-performance tires (a high-end highway tire) are popular
choices for many passenger cars, but they would fare poorly
on secondary roads. "These tires are made with softer rubber
compounds to help them adhere to the road, but they are more
vulnerable to chunking," explains Jaye Young, senior brand
category manager for Michelin North America. "Their shorter
sidewalls help the vehicle handle corners faster, but that
makes the sidewalls susceptible to damage on rough, uneven
surfaces."