Some fleet managers squeeze the beaver on every nickel till they, well, you know. Others, thanks to misinformation or indifference, let too many of the critters get away. Take tires - overhead item number two after fuel: Fleets can save a lot of m...
Some fleet managers squeeze the beaver on every nickel till they, well, you know. Others, thanks to misinformation or indifference, let too many of the critters get away. Take tires – overhead item number two after fuel: Fleets can save a lot of money with good tire management programs, with retreads as the thick frosting on the cake, but many are not doing it.
“I know one fleet that buys all new tires and says retreads have a bad name,” says Bill Spence, of Bill Spence & Associates Inc., a maintenance consulting firm, headquartered in Carlisle, Ont. Yet when he worked with Ryder, the company was recapping 20,000 tires a year.
There may well have been a time when retreads deserved a bad rap, but nowadays, any prejudice against retreads is “for no good reason,” writes Harvey Brodsky, the managing director of the Tire Retread Information Bureau (TRIB) in an article on retreads.
Those “alligators” we have all seen on the highways are just as likely to have peeled off a new, or too-old tire as off of a properly-maintained and recapped tire. Dead alligators tell no special tales about retreads, but they confess plenty about poor tire management practices.
After listening to Spence talk tires for a while, his reasoning for favoring retreads can be distilled into one short pitch: A new tire can cost $400, a retread can cost $150 and a retread can get the same mileage as the original tire. What more is there to know?
Plenty, actually, because for casings to be fit for retreading, they first have to survive for years and hundreds of thousands of kilometres of sometimes friendly, sometimes nasty, driving. Survival is best achieved with a tire management program. Retreading, it turns out, is not the sermon, but rather the occasional “hallelujah!” that keeps the congregation awake.
The sermon is about getting as many safe kilometres out of your new tires as possible while minimizing abnormal wear and tear, then pulling the casings at the right time, passing the retreaders’ inspections that qualifies them for recapping, then running the recapped tires. Repeat several times and declare your tires to have run for the lowest possible cost per kilometre.
Spence divides tire management into four categories: buying tires, maintenance, recycling and tracking: When selecting the overall tire and tread designs for the fleet’s various applications, consider the vehicle type and application, the vehicle load, who to buy from, what tread to select and the warranty. Some OEM tires recap better than others – intelligence that OEMs will happily share, but poll some retreaders too. Some casings are worth more than others, if you intend to sell them rather than recap them for yourself.
The wrong tires and treads for the application are tire killers; e.g., city P&D will quickly wear down long-haul tires and can cause sidewall damage making them unfit for capping. “A lot of fleets are very knowledgeable about tires times application, but I see the wrong tire for the application a lot,” says Spence. “When you order the truck you need to specify to the chassis OEM the application.”
Pick a primary tire OEM and do not mix brands on the same axle, Spence advises. It is also wise to have a tire test program on the go to ferret out higher-performing tires, maybe at a lower cost. “You should always have at least three new tread designs, outside your favorite [OEM] brand, being tested at one time,” Spence says. Spec identical trucks and make sure they do the same work and get an OEM to help set up a test program; this is no simple altruism, as OEMs need fleets to road test tires under real-life conditions.
Michelin, for example, has been road testing its wide base X-One XDA with several fleets. Quebec’s Groupe Robert, which has been using the X-One XDA on the quad trailer self-steering lift axle, made an important discovery: this axle, which was new equipment for them, requires far more careful alignment than expected to obtain satisfactory tire life, according to Franois Gareau, Robert’s tire manager.
This discovery illustrates the importance of maintenance, the absolutely most important part of which is tire pressure. Bridgestone says that a tire under-inflated by 10%; e.g., 90 psi instead of a recommended 100 psi, will wear out 9% to 16% faster. Yet improper inflation is a notorious problem, especially for the tires furthest away from the driver side cab door.
Improper inflation has many downsides, all of which shorten tire life and may disqualify them for recapping; by the way, the casing rejection rate is 15-20%, according to Spence. Under inflation causes excessive deflecting, or bending of the sidewalls. This can damage the steel cords, overheat and prematurely age tires and cause irregular tire wear. Over inflation causes wear in the centre of the tires and makes them more susceptible to puncture.
Checking tire pressure by kicking them or whacking them with an iron bar is about as useful as stargazing from a hall closet. A calibrated gauge is the tool of choice, and each shop should have a master gauge against which to check them, Spence advises.
Work with the tire provider to come up with the tire pressure for the tire and the application. Get free decals, write in the recommended tire pressures and stick them on the lower left hand corner of the door or the lower corner of the cab extender, or on the lower left side of the trailer between the duals.
Inspect valve stems and caps, because that is where tires are most likely to lose air. You can cut the time it takes to check the tire pressure on an 18-wheeler to just 10 minutes with a flow through valve cap, according to Spence. At about a dollar apiece, they let you inflate or deflate the tire without having to remove valve caps.
You should do one X rotation of the drive tires when the difference in the depth between the front and rear axle is more than 4/32″. Do not allow more than 8/32′ between the dual matings, or the smaller tire will scrub. Alignment is important too and for about $2000 – the cost of five tires – a fleet garage can buy the equipment to check wheel alignment, even if it hires out the actual alignment work to another shop, Spence suggests.
Then there are pull point standards: Don’t run the tires down too far, otherwise you’ll ruin the casings, says Spence. “Pulling tires early enhances retreadability. As a guide, the drive tire should be pulled at no less than 4/32-5/32 of an inch.” And if you delay? “Another month of use can cause you to lose a casing. The best [prevention] against punctures is adequate tread,” Spence says.
When tires are pulled, the mechanic should put a unit number on it, so if a problem surfaces, he can go back to the truck and try and find out what caused it; problems may not show up until the retreader inspects the casing. For example, he might find a lot of nail holes that may be traced to the practice of sweeping out trailers, nails and all, at fuel islands. Damaged tires and wheels should be removed before the damage becomes too extensive to make retreading possible.
Bandag writes that, as a rule, fleets should put a five- to six-year age limitation on casings. Too much more than that is pushing your luck and three to four years is probably denying yourself some return on investment (ROI). Combined with a good tire inflation program, you will get good ROI and not unduly expose yourself to highway tire failures.
Regularly double check your “knowledge” too. TRIB’s Brodsky discovered that many truckers believe that retreads should be run below the OEM-recommended pressures: He recounts folk wisdom like, “We always run retreads at 10 pounds less than new.” That, he says, is “absolutely not based on fact.”
Tire tracking is a neglected area of tire management, according to Spence. He recommends always having high-mileage tires that are casing generators, to keep the casing inventory high enough. Put new tires on the high-mileage trucks. First retreads might go on drive tires, and as the number of times a casing has been capped increases, the more you will want to run them for regional, local or even yard duty.
If your fleet has no tire manager – they are rare and tight-lipped too, the TRIB Website (www.retread.org) makes excellent reading; e.g., where to find retreaders in Canada and the US, tips and articles from OEMs on tire management, retreading and a primer on casings.