By knowing when the tires on your company's vehicles need attention, it is possible to save money and avoid expensive downtime caused by flat tires and missed or late appointments.

Winter driving conditions may vary in different parts of the nation and at different times of the year, but tire wear and care needs never change. From front-end misalignment, damaged or worn suspension components, and improperly balanced tires to bent tire rims, or under-and over-inflation of tires, it's important to be able to spot the warning signs. By knowing when the tires on your company's vehicles need attention, it is possible to save money and avoid expensive downtime caused by flat tires and missed or late appointments.

Telltale signs of tire trouble include the following symptoms:

• Edge wear: When the inside and outside edges of tires are worn, it generally indicates an under-inflated tire or hard cornering.

• Center wear: An over-inflated tire typically shows worn areas in the center.

  Shoulder wear: A thin line of wear on the shoulder side usually indicates a misaligned tire.

• Irregular patch wear: Flat spots and patchy or scalloped wear generally indicates improperly balanced tires or those that have damaged or worn suspension components.

• Worn tread: Narrow strips of smooth rubber across the tread are known as "wear bars," indicating that the tire needs to be replaced.

• Worn edges and sidewalls: When this occurs early in the life of new tires, it is a major warning sign that the vehicle is being consistently overloaded for the tires' load-carrying capacity.

In addition, tires that are well maintained will go the extra mile in delivering maximum value. Maintaining good driving habits, avoiding fast starts and hard stops, parking carefully away from curbs, and avoiding potholes when possible will all contribute to extending the life of the tire. There also is no substitute for good maintenance measures:

• Observe guidelines for inflation pressure. Using a quality tire gauge, check tire pressure at least once a month and before any long road trips. The best time to check pressure is when tires are cold. For the proper cold-tire inflation pressure for individual vehicles, check the owner's manual and/or the tire placard located inside the front driver side door.

• Rotate tires regularly. Just rotating tires regularly can extend tire life by as much as 20 percent. A good rule of thumb is to rotate tires during every other oil change, or more frequently depending on driving habits and road conditions. A rotation schedule may be suggested in the owner's manual.

• Inspect tires monthly. Check tires on all vehicles monthly, paying particular attention to signs of wear or visible damage, as well as ensuring that all valve caps are in place to help keep out dirt and moisture.

• Maintain vehicles "by the book."

Because many vehicle components, including shocks, struts and brakes, can affect the tire's performance. Ensure company vehicles are inspected regularly and follow the recommended maintenance schedule listed in the owner's manual or provided by your fleet maintenance management provider.

Because tires are the only thing separating vehicles from the road, it is extremely important to make sure they are in the best possible condition at all times. Manufacturers emphasize the need to select tires of the same brand, line, size, speed rating, load index and load range when replacement is needed. Failure to use equivalent replacement tires may adversely affect the safety, handling and vehicle performance.