Every vehicle sold in the United States comes with an owners’ manual. The manual tells the driver everything he/she needs to know about the safe operation of a vehicle, including the recommended rotation of tires. Tires need to be rotated on a regular basis, because, depending on the tire location, tire treads wear differently. For instance, a passenger car has much more weight over the front tires than the rear. Also, tires are designed to contemplate the camber, or angle, of a given tire location. Without rotation, a vehicle’s tires will wear differently, irregularly, and dangerously.
A vehicle’s owners’ manual will provide a recommended rotation schedule. Many tires are designed to operate for 60,000 miles. But, without rotation, tires will simply not make it that long. Without rotation, a driver may find his/her front tires wearing much faster than the rear tires. Additionally, because of camber, a driver might find his/her tires wearing much faster on one side than the other. Because of these concerns, vehicle manufacturers advise consumers to rotate their tires to ensure an even wear on all four of their tires. A four-tire rotation is recommended for vehicles with a “donut-spare”. Donut-spares are designed for emergency use only. Moreover, it is highly discouraged to operate donut-spares at highway speeds, because they are not designed with a speed rating that can endure the forces associated with highway driving.
Many vehicles possess a “full-sized spare”. A full-sized spare has no operating restriction similar to the donut-spare. Instead, tire manufacturers expect the full-sized spare to eventually rotate into service and operate as a fully-functioning tire use during regular operation. For this reason, vehicles with a full-sized spare tire should utilize a five-tire rotation. By not incorporating the spare tire into the rotation schedule, the spare never wears commensurately with the other four tires. Most importantly, the spare tire should be included in tire rotation, because an inactive tire presents latent danger. Most people think a spare tire that has never been used is a new tire. This is not true. Tires are, regardless of use. Our firm represented a family of a young woman that died during a tread separation accident while she was driving home from tire maintenance. The tire that failed was a 6-year old spare tire that had never been used. Despite possessing the nipples characteristic of a new tire, the unused spare failed because of previous dormancy.
Tire manufacturers design tires with the understanding of the constant forces applied to operating tires. They understand tires are living beings that need to have forces exerted on them to maintain their integrity. Take a rubber band, for instance. If you placed a rubber band in the sun, or otherwise expose it to the elements, the rubber will age, becoming brittle. When needed to stretch, the rubber band will break. Contrast that with placing the rubber band between your thumb and forefinger, consistently stretching it over 30 days. On the 31st day, the rubber band will continue to stretch as designed. But, the rubber band left in the elements for 30 days will fail when asked to stretch on the 31st day. Tires, like rubber, age. They need operation to maintain their integrity. Always incorporate a spare tire into a regular tire rotation schedule.
Written by:
Guy L. Watts, II
Watts Guerra LLP
4 Dominion Drive, Bldg 3, Suite 100
San Antonio, Texas 78257
Phone (210) 447-0500
© Watts Guerra LLP 2015
