Inspecting tires on a routine and regular basis is the key to succeeding in maximizing your tire removal miles. Drivers, technicians, and outside vendors who service your vehicles can all play a significant role in getting the most miles out of your tires.
The goal of every tire program is to ensure that the tires are running smoothly and evenly without irregular wear. Fuel economy is maximized when tires are running without irregular issues such as shoulder cupping, one-sided wear, fast shoulder wear on both shoulders, and heel/toe wear. Fuel economy will be adversely affected and tires will be removed prematurely due to uneven wear; and the cost/mile will show a dramatic increase.
Training drivers, technicians, and your vehicle servicing network will go a long way to maximizing tire removal miles with the side benefit of fuel economy improvement. A serious on-going tire training program is essential and should include identifying specific wear patterns, their probable cause and how to correct the issue. A few facts your training should include:
Steer tires develop different wear patterns versus drive, trailer, and dolly tires. Sometimes the irregular wear can be directly related to the vehicle alignment. Many times too much wheel-end play and worn suspension components can be the leading cause.
Underinflated tires will lead to significant irregular wear since the tire footprint becomes longer and distorted. The added heat due to a combination of excessive idewall flexing and the longer footprint (more rubber on the road) can also lead to major irregular ear and even tire failures.
Another major reason tires develop irregular wear occurs when vehicle loads change. Since air carries the load, the tire pressure specification must be based on the worst or heaviest load scenario. Fleets running 100 psi loaded could run somewhat less pressure unloaded, however, the higher the pressure the more it benefits fuel economy, which more than offsets the slight tire wear in unloaded back haul situations.
Checking tires with a calibrated pressure gauge will identify tires running out of spec. The more frequently your team can check tire pressures, the better. In the real world, just because you checked tire pressures before leaving the yard it has minimal benefit when the vehicle runs over a nail just a few minutes later.
Never take air out a hot tire as a hot tire is running about 15% higher pressure than the “cold” or room temperature pressure setting. Tires take four to six hours, depending on the size, tread depth, materials and tire pattern before cooling back down to its cold pressure setting after running on the highway fully loaded.
From the Commercial Fleet Tire Digest, published by Pressure Systems International, the maker of the Meritor Tire Inflation System by PSI. Used with permission.