Hands-Off Tire Inflation
Drivers should be steering freight, not kicking tires.
Mark Putz
Associate Editor
Keeping tires properly inflated is a job often shouldered by drivers. Drivers are often seen as the first line of defense against the high cost of low tire pressure. But this may be changing. Driver-based pressure checks often amount to kicking, thumping, or merely eyeballing the inside tires during the pre-trip walk around. A better scenario sees daily pre-trips reinforced by a weekly pressure check, with the driver sticking each tire with a gauge. This takes about 20 minutes. Doesn't sound like much, but that's time subtracted from the new 14-hour day — a potentially precious chunk of minutes. Add to this the fact that policing driver inflation-maintenance is not always practical.
That's why many fleets are taking drivers out of the inflation equation. A new pattern in the industry sees the driver removed from the hands-on maintenance.
The Technology & Maintenance Council calculates that trailer tires lose air pressure at a rate of 2 to 3 psi per week — parked or moving. There are a variety of systems on the market that monitor inflation, alerting to the driver to the current tire pressure. For example, Doran Mfg. offers a wireless tire pressure sensor that screws onto the valve stem of each tire. The sensor matches the wheel position, sending a wireless signal to a receiver that tells the driver which tire has low pressure. With this type of system, a sensor sends an alarm if the pressure drops a below a percentage-based setting. These systems are better than the thump-and-kick routine, but still require hands-on action by the driver. The driver must manually correct the pressure, introducing the possibility he'll monkey with tire pressure to suit his "soft-ride preference."
Constant Air
Fleets that want drivers one-step removed from the inflation loop are looking at constant air systems. Systems that automatically maintain tire pressure from the trailer's air system are often touted in terms of reducing blow outs and downtime. But what these systems really offer is accurate, day-to-day maintenance — with the resulting time savings. And since new hours of service rules make driver labor more expensive than ever, these systems are becoming more popular.
When a driver grabs a trailer in the yard or at a customer's location, these systems automatically fill any pressure discrepancies. By replenishing tire pressure of a dropped trailer during pick up, fleets save the labor and cost of inflating trailer tires at an outside service. A trailer equipped with a system such as PressureGuard from Ohio's Reineke Co. Inc. even has an option that notifies dispatchers via satellite e-mail regarding system status. If a moving trailer has a low-pressure situation, a dispatcher is made aware of the problem.
One concern with any automated inflation system is maintenance on the road. If a tire catches a nail in Needles, Calif., you want the service person to be able to properly reinstall the system. Reineke says it handles any information gaps with decals above each wheel well. "Our system's quick connect is very simple, and the decal serves a reminder."
PressureGuard's valve stem adapter has a triple-seal design with a locking nut. Once installed properly, Reineke says it ensures a leak-free connection for the life of the tire. The system also touts quick disconnects at the valve stems.
During routine wheel end work and tire changes, quick disconnects eliminate the time-consuming dismantling of the tire inflation system, and the aluminum hubcap with integrated air channels and ribs prevents valuable components from being damaged.
Manufacturers of these systems say that fleets wanting to keep drivers out of the inflation game have the system pre-set — they can't be adjusted by drivers.
With this in mind, Airgo says its system is set for customers during installation or by shop personnel. At the same time, over-the-road service people are finding tire and wheel maintenance easy, according to Airgo's Dale Lane. "You unscrew the hose. Nothing other than that."
Adjustable Air
Like the constant air systems, adjustable systems tout serviceable designs. And pressure maintenance for tire safety and longevity is not the only benefit provided by an adjustable inflation system. For example, Dana Spicer Tire Pressure Control Systems provide adjustment of tire pressures for enhanced traction effort. The system allows the operator to select one of four terrain settings via pushbutton controls in the cab, and then inflates or deflates the tire pressure to match the terrain and load. In addition, the system can be configured to control differential locks and interact with other vehicle sub-systems to enhance overall vehicle mobility.
Application will dictate the appropriate inflation system. But with rising labor and tire costs, you should know that the centralized-inflation options are growing.
