“You have to watch them, you have to have a visual inspection, you need to measure your tread depth and understand if you’re in compliance with your own program,” he says.
“Some guys find that balanced tires wear a lot better in their application than tires that aren’t balanced,” says Sweatman. “Matching, rotation, there are just so many things that you have to watch to establish these pull points. As long as you’re still getting the performance characteristics that you’re looking for. You don’t want to sacrifice traction for fuel economy by running tires down too far.”
RELY ON YOUR DEALER
Eugene Johnston, manager of business development for retreader Bandag, Incorporated, suggests that tire dealers may be better judges of when tires are ready to be retreaded.
“Most fleet managers think about their trucks in terms of PM schedules, and most of their PM work is focused around the engine, and engine PMs are generally handled by mileage,” he says. “How many miles do you have on the truck? Every 15,000 miles you might get an oil change, for example; they don’t have an indicator like tread depth on an engine that tells you when it’s time to get an oil change or it’s time to flush the radiator, so they’re used to using mileage and/or time periods. In fact, much of the software fleets use to schedule maintenance intervals is based on mileage or calendar time.
“If you have a tire dealer doing that work for you, they’re going to base it on tire-related criteria,” he says.
But for fleet maintenance managers who prefer to do their own tire work in-house, Johnston has this advice: “If he has the capabilities—and this does depend on the people and the systems he has available to him—he should be using tire inspection criteria from the TMC (Technology & Maintenance Council). They have Recommended Practices; they can go there to see what conditions would justify removing a tire from service because of damage or weather cracking or whatever other conditions there may be.
“But when it comes to tread depth and wear, ideally they would look at tread depth rather than mileage or months in service,” he says. “You want to make sure that the next time that truck comes in for maintenance, the tread is still well within the legal limit for tread depth.
“At the bare minimum, you want to make sure that you’re not going to be taken out of service by a DOT inspector or a CVSA guy for being too thin on the tread,” he says.
SET YOUR LIMITS
In the end, it’s up to you to decide the proper tread depth at which your technicians should be pulling tires for retreading.
Equally important, Johnston stresses, is deciding how many times you want to retread your casings: once? twice? three times? “My advice is to take all your tires that are in reasonable condition, send them to your retreader and let him decide which ones are retreadable,” he says.
If you “judge each tire on its own merits,” as Johnston says, you should never have to worry whether you’re retreading too late, or too soon.