The cause of maintaining proper tire inflation pressures will never die. 

If you were to create a top ten list of the most hated jobs in the shop, checking tire inflation pressures would probably rank in the top five --- and maybe even number one. How do we know this? Easy! If people liked to do it, there would rarely be a tire problem related to inflation or the lack thereof. 

Now, on a pleasant summer afternoon with sunshine and light breezes you could probably talk to everyone in the shop into going out and checking tires. But let's face it, tires need to be checked every day, and it's no fun crawling around duals in a Kansas downpour or in the dead of winter in upstate New York. 

While fuel remains the number one fleet expense, it is not a maintenance cost. Tires, which represent 20% of the total vehicle maintenance cost, are the major maintenance cost for fleets. Managing tire costs is an important issue for every fleet. 

We recently reported that out of 55,000 emergency road calls for fleets, 50.1% were related to tires. That number not only represents a significant expense for unscheduled maintenance, but also becomes an escalating expense, when driver time and load delays are factored in. According to Al Cohn, Goodyear Rubber & Tire Company, "The industry average time for vehicle downtime is over two and one-half hours. Time is not only money, but it costs your company future business opportunities." 

Speaking at a recent presentation at The Maintenance Council (TMC) on tire basics, Cohn went onto say that underinflation of tires leads to such problems as irregular wear, reduced fuel economy, reduced casing life and reduced removal mileage----saying that 20% underinflation will cost a fleet 12 to 16% in reduced miles. 

Guy Walenga, Bridgestone/Firestone, who also spoke at TMC, says selecting the right tire is the second most important step to getting a return on a tire investment----maintaining proper air pressure is number one. 

Most fleets are well aware that running on tires that are not properly inflated has many drawbacks. First of all, it can be dangerous. Then there are related costs such as a reduction in tread life (by as much as 25%) and increased rolling resistance, which makes engines work harder and burn more fuel. Add to all of that reduced casing life, which diminishes returns for retreads. Tires require the proper inflation pressure to carry the vehicle load. If tires are run in an overinflated state, the ride is hard (taking a toll on drivers, load and equipment) and they will develop centerline wear and end up being removed prematurely. 

Checking air pressure differs from fleet to fleet and application to application. Fleets that do a lot of city driving and secondary/off road travel need to check air pressure more frequently than a fleet in line-haul operation. A basic rule of thumb is to check air pressures in all positions once a week. However, encourage drivers to "look" at tires daily to check for abnormalities.

Teach drivers to do a quick visual tire inspection to check for: