PSI MEANING IN TRUCK DRIVING MANUAL

When they do, it’s usually because of some external factor, such as an alignment problem or a road hazard. Summers’ fleet target for drive tire life is 450,000 to 500,000 km, and he hardly ever sees tires that deliver less. If you see a rounded footprint, you are going to get irregular wear on the edges, which shortens tire life, and you get less traction because the portion of the tire in contact with the road is smaller, especially when you’re lightly loaded.” “If you over-inflate the tire, the footprint becomes rounded at the sides and the front and rear. “A flat, square footprint is what you want for even tread wear,” Summers says. He says it’s all about the tire’s footprint or contact patch. Similarly, Brad Summers, the shop manager at Liberty Linehaul - also of Ayr, Ontario - runs 90 psi in both his drive and trailer tires. Reavely says he hasn’t lost a drive tire to irregular wear since 2018, and he doesn’t see the stone drilling issues other fleets report with those tires. We’re getting really even treadwear straight across, and a better footprint on the road.” “You don’t need anything close to 100 psi with the weights we run, so we discussed what the optimum pressure should be based on their engineering and experience, and 85 psi seems to be the magic number for our drive tires. “We worked closely with our tire vendor to come up with those pressures,” Reavely says. Even a 5-psi delta can make a difference. It’s easy with an automatic tire inflation system, but not so easy with drive tires. Equalizing pressure between dual tires is the best thing you can do to reduce irregular tire wear. He runs 85 psi in his drive tires and 90 or 95 psi in his trailer tires, adjusting the pressures for seasonality. No tire pressure monitoring system or automatic tire inflation is involved.

PSI MEANING IN TRUCK DRIVING MANUAL

The related tire program includes annual three-axle tractor alignment, annual replacement of the shock absorbers, and regular manual tire pressure checks. His fleet gets 500,000-575,000 km out of drive tires. How does one coax more than half a million kilometers out of a set of drive tires? You pay attention to them, advises Mark Reavely, fleet maintenance manager at Trans-Frt McNamara of Ayr, Ontario. Drive tires running to 800,000 km are not unheard of in these two fleets. They report tires running out to 400,000 and 500,000 kilometers before coming off the truck. The two fleets we interviewed for this article are running 85 psi and 90 psi in their drive and trailer tires in longhaul Canada-U.S. If you are arbitrarily inflating your drive and trailer tires to 100 psi, you might be giving up a little or a lot of both. Tire inflation pressure affects the footprint of the tire, traction, and tire life. The number is easy to remember, but you may be sacrificing miles-per-32nd for the sake of convenience. Evidence suggests the set-it-and-forget-it, all-position, one-size-fits-all inflation pressure of 100 psi is not the best way to maximize tire value. Tire inflation pressure is a real conversation killer at a party, but it’s something fleets should be talking about with their tire vendors, shop personnel, and drivers.

Psi meaning in truck driving