Tires are among the costliest items for any fleets' operations, right behind labor and fuel. “In just the past year, we've seen tire costs go through the roof,” says Sam Lamerato, superintendent of fleet maintenance for the City of Troy, Mich. The 38-year veteran should know. In 2010, Troy headed Government Fleet magazine's list of the 100 Best Fleets in North America.
To keep these costs under control, Lamerato has established a structured maintenance routine for the city's 500 pieces of equipment — ranging from passenger and police cars to fire apparatus, heavy-duty on-highway, and off-road vehicles. Light- and medium-duty tire service is done in-house, including breaking down, maintaining, and installing wheels and tires. Whenever a vehicle comes in for its preventive maintenance service — consisting of lube, oil, and filter change and general inspection — the tires are inspected. All of the data is entered in a computerized fleet maintenance program.
Lamerato's technicians used to check torque on all wheel nuts as part of their preventive maintenance — until he discovered Wheel-Checks. The plastic arrows fit snugly around wheel nuts after they've been torqued to specification. The arrow or indicator portion of each Wheel-Check is aligned to either point to the next nut, thus forming a circle, or to point perpendicular to the wheel rim. If a nut starts to loosen and back off, the change in the arrow's direction is readily visible. “They have saved countless hours of retorqueing,” he says.
The Wheel-Checks also start to change color and blister when they are heated above 250° F. That gives maintenance personnel an indication that a bearing is failing or a brake is dragging before any major damage is done to the wheel, hub, tire, or brake.
Lamarato saves money by using a single, state-approved provider, Belle Tire, for the fleet's remaining service needs. He purchases all tires — 90% of which are Goodyear — from the vendor, which also handles the city's road service calls and heavy-duty service.
“Belle is also a Bandag retread dealer and we recap our tires whenever we can. It can save up to two-thirds of the tire cost,” he explains. Each week, Belle picks up the fleet's worn tires for recapping and returns the last week's retreads.
“You can't really separate tire maintenance and wheel maintenance,” says Lamerato. His fleet uses 11R22.5 tires on its on-road heavy trucks and up to 12R25.5 for off-road vehicles. With more distance between the tread and rims, the larger tires help protect the wheels in off-road situations and when running on some Michigan roads that aren't in the best shape. Damaged and rusted rims can leak air and damage the tire at the bead. Belle Tire treats the rims with an abrasive blast and reconditions them. They also inspect for cracks at the stud holes and reject damaged wheels.
Brushing up: maintenance resources
Fleets seeking to upgrade their tire management program will find a great deal of guidance in the Recommended Practices Manual issued by the Technology and Maintenance Council (TMC) of the American Trucking Associations. Reference materials produced by the council's Wheel and Tire Study Group include:
- Radial Tie Conditions Analysis Guide (RP 216C)
- Radial Tire Wear Conditions and Causes: A guide to wear pattern analysis (RP 219C)
- The User's Guide to Wheels and Rims (RP 222C)
- Outsourcing Guidelines for Tire and Wheel Maintenance (RP 236) helps fleets evaluate whether or not to out-source wheel and tire work or keep it in-house. It also provides checklists for defining roles and responsibilities.
- Torque Checking Guidelines for Disc Wheels (RP 237A) reviews factors affecting clamp load and proper torque wrench use. The guidelines caution against using torque-limiting adapters, or torque sticks, that twist to absorb a portion of the torque generated by air impact wrenches. The tools prevent gross overtorquing, but can be inconsistent.
- Retread Plant Inspection Guidelines (RP 221D) cover everything from planning the visit to evaluating operations. Before instituting a tire retreading program, the Tire Retread and Repair Information Bureau, the Retread Tire Association, and TMC all recommend visiting the facilities that will work on your tires.
- Industry Advisory for Retreading Truck and Bus Tires (RP 212C) is a must-read for fleets involved in retreading. It discusses casing selection and criteria for submitting tires to be retreaded.
I have found the TMC Recommended Practices Manual to be a valuable guide for all aspects of vehicle maintenance — not just tires. To purchase a copy, call 703-838-1763; a free CD is provided with council membership.
— Paul Abelson (firstname.lastname@example.org) is a former director of the Technology and Maintenance Council (TMC) of the American Trucking Associations, a board member of Truck Writers of North America, and active in the Society of Automotive Engineers.
To see a slideshow of the retreading process from “Rethinking retreads,” May 2011, click here.