A research project recently completed by the U.S. DOT proves that tire inflation systems and tire pressure monitoring systems can help reduce fuel consumption and improve tread life while lowering tire maintenance costs.

Chris Flanigan of the Federal Motor Carrier Safety Administration's Office of Analysis, Research and Technology shared the results of the agency's Tire Pressure Monitoring Field Operational Test during an S.2 - Tire and Wheel Study Groups Session at the Technology and Maintenance Council annual meeting in Tampa, Fla., last week.

"The program goals were to assess the cost/benefit, to determine if the systems could influence maintenance intervals in a positive way and to determine their impact on performance and safety," Flanigan told the group.

"We saw an increase in fuel economy in both fleets of 1.4%, which is a big deal," he said. "And based on current fuel costs [about $4.00/gal] and equipment costs of about $1,500 per tractor-trailer unit, the ROI comes in under one year."

The DOT conducted the tests between April 2008 and December 2010 using two fleets: Sheetz, a fuel distributor based in Altoona, Pa., and Gordon Food Service, a curbside delivery fleet from Grand Rapids, Mich.

The Sheetz fleet had 10 tractors equipped with the Integrated Vehicle Tire Monitoring System from Wabco, and 10 tank trailers equipped with Meritor Tire Inflation System (MTIS) by PSI.

The GFS fleet had 12 tractors and 15 trailers equipped the Tire-SafeGuard tire pressure monitoring system, along with 20 trailers fitted with MTIS.

Researchers recorded daily mileage as well as fuel consumed, and to the extent possible did daily tire checks and systems status updates, looking for fault codes, signs of system activity and driver warnings. As well, technicians took regular tire pressure and tread depth measurements so they could evaluate and compare the three systems in use.

Over the course of the test, the Sheetz fleet ran 3.9 million miles, consumed 632,000 gallons of fuel, and saw 162 tires replaced for wear. Overall, they recorded 38 tire incidents. The GFS fleet ran 3.4 million miles and burned 520,000 gallons of fuel, and saw 278 tires replaced. GFS had 77 tire incidents.

Flanigan says the results showed both fleets experienced an equal reduction in fuel consumption of 1.4 percent. Tread wear reductions recorded in the Sheetz fleet were notable. Steers tires saw an improvement in tread wear of 5/32 per million miles and trailer tires saw an improvement of almost 2/32 on an inch per million miles. The drive tires, however, improved by nearly 30/32 per million miles.

Overall, Flanigan said the test was a very positive experience for both fleets.

"Technicians and managers at Sheetz liked the system a lot," he says. "They had confidence in the system. And my understanding is, three months into the test they began purchasing the system for trucks that were not involved in the test,

"At GFS, technicians and managers were pleased with the systems' ability to reliably detect tire failures and provide accurate tire pressure measurements. Drivers who were initially a little wary of the systems eventually asked management to equip entire fleet with TPMS and ATIS at the conclusion study."

For more information on the equipment tested:

Valve Stem Mounted TPMS -- 10 Sheetz tractors
Integrated Vehicle Tire Monitoring System (IVTM)
www.wabco-auto.com/ivtm

Wheel Mounted TPMS -- 12 GFS tractors, 15 GFS trailers
System Installed: Tire-SafeGuard Monitoring System
www.tiresafeguard.com

Meritor Tire Inflation System (MTIS) by PSI -- 10 Sheetz trailer, 20 GFS trailers
www.psi-atis.com