Tire Pressure Monitors
These days, fleets can select systems ranging from the relatively simple to the very sophisticated.
Evan Lockridge
Contributing Editor
A good fleet manager or technician already knows one of the many aspects of a good tire maintenance program is making sure air pressure is checked regularly. For fleets with trucks on the road for weeks at a time, part of making such a maintenance program work is getting drivers involved in the process - often easier said than done.
Fortunately, there are new and better ways of keeping a check on tire pressure other than relying on a driver with a tire pressure gauge. And you can select systems ranging from the relatively simple to the very sophisticated.
Tire pressure monitoring systems differ from tire inflation systems. Tire inflation systems, such as those marketed by ArvinMeritor, Hendrickson, Airgo and Dana, not only monitor a tire's pressure, but they also automatically keep tires inflated to the proper level.
However, such systems are mainly available for use only on trailers. Even though tire pressure monitoring systems require someone to physically put air in the tires, they can monitor every tire on a tractor-trailer, letting drivers and technicians know when a problem exists.
Tire monitoring systems come in variety of types and price ranges, so almost any fleet can find something for their budget. Some are very straightforward, with in-cab devices that let a driver know when a tire needs air. Others are more high-tech, with wireless devices that can check air pressure and computers to track tire trends.
Among the most ambitious products you'll find are those from Michelin and Stemco.
Michelin's eTire system was introduced just over three years ago. It uses an in-tire sensor and either a wireless hand-held unit or drive-by reader. An in-tire sensor relays not only tire pressure to either the hand-held unit or the reader, but also tire temperature. Users can manually input other information, such as vehicle mileage, allowing a tire to be tracked through its entire life, including through the retread process. All of the information is then uploaded to Michelin's web-based computer software.
"This program allows the maintenance manager, tire technician or anyone involved with the fleet, to go in and mine that information," said Nate Leehman, manager of tire electronics at Michelin. "This allows them to get immediate feedback that the tire was properly inflated, over-inflated or under-inflated. That information is also stored so they can track the history of that tire, such as was it under-inflated multiple times, is it a slow leak or some other problem."
The system is unique in that it reads tire temperature. This allows readings to be taken if a truck is pulled straight off the road, because eTire relays cold tire equivalent pressure. And because the computer program that tracks the information is web-based, it can be viewed by fleet managers anywhere and anytime.
The latest entrant in high-tech tire pressure monitoring is Stemco and its BAT RF, introduced in February. Though only available for use on dual wheels at this time, the system uses a unit called AirBAT that attaches to the wheel end, with hoses that lead to the valve stems to monitor pressure. This unit conveys tire pressure - along with date, time and information identifying what truck the unit is on and in what position - to a wireless hand-held device called the HandBAT. There is an option called the TracBAT that measures mileage, which can be read directly off the unit or conveyed wirelessly to the HandBAT.
"The BAT RF system is not tied to the tire and can be transferred to another vehicle," said Ken Veit, director of business development at Stemco. "The information from the HandBAT can then be downloaded to a PC and can be used for analysis in a program called DataBAT."
Information from DataBAT also can be exported to popular spreadsheet and database programs such as Excel and Access for analysis by fleet managers.
Veit said plans are in the works to expand the system so it can be used on all tires, including wide-based singles, by late summer or early fall. A web-based analysis program is also planned.
Neither the Michelin nor Stemco system offers in-cab monitoring of tire pressure, leaving the responsibility to technicians at truck terminals. However, if your operation calls for drivers to keep tires inflated on the road, there are several devices that let a driver know immediately if a tire is low. Units such as these do not offer any sort of computerized analysis programs, but they do offer immediate notification to the driver once tire pressure starts to drop.
Doran Manufacturing's PressurePro was introduced about a year ago. It uses a dash-mounted receiver and sensors that mount in place of the valve cap on each wheel. Tire pressure information is transmitted wirelessly from the tire to the in-cab receiver. When tires drop 12% below their proper pressure, an audible alarm is sounded for the driver, a corresponding LED flashes on the panel showing which tire is low, and the tire pressure for that particular tire is shown on the in-cab display. At a 25% drop, the same information is shown, but the audible alarm beeps faster.
"This system not only allows you to monitor tires when you are going down the road, but you can get a digital readout as to what the tire pressures are as part of a pre-trip or post-trip inspection," said Chris Nau, outside sales engineer for Doran. The PressurePro system can be used for all tires, including those on medium-duty trucks.
A similar device is sold by Fleet Specialties under the name Tire Sentry. It too uses devices that go on the end of the valve caps and wirelessly transmit information to an in-cab receiver, but it only shows which tire is losing air pressure, not what the actual pressure is.
Even if you are already using or thinking about using a tire inflation system, you may want to consider tire pressure monitors because tire inflation systems are generally not available for tractors. This additional investment for your power units may be worth your while, depending on your circumstances. And if you're running single-wide tires, it's even more important to make sure they are running at the proper pressure, because you can't limp along on a flat like you can with duals.
What kind of tire pressure monitoring system is right for you depends on several factors, including what kind of hauling you're doing, how often trucks return to terminals, how large your fleet is, and of course how much you can spend. Keeping tires optimally inflated will save you money in the long run.
And having the right kind of system for your operation will make for a greater return on that investment.
