What's the solution to keeping tires inflated properly?

Carl Tapp, Vice President of Maintenance, P.A.M. Transport: "For our trailer tires at least, it's an automatic tire inflation system (ATIS). It's not unusual for our trailers to sit for 2-3 weeks before being picked up. On top of that, sometimes it's months before we see those trailers in our lot.

"And, you're just dreaming if you think the first thing the driver is going to do when he picks up a trailer is check the air pressure.

"So, we've added ATIS to about 3,000 trailers. I've been investigating these systems since 1987, and we've just about tried them all."

Is automatic tire inflation working for you?

"It's very successful. We've done a number of studies on it by keeping track of all of our tire expenses on trailers with and without ATIS.

"What we did was record every expense that comes under ATA VMRS Code 1700 for both control and test groups.

"The results are astounding. We've seen tire cost advantages of as much as 70 percent with ATIS. And it's probably a good bet that you could consistently save around 50 percent."

Where do the savings come from?

"We can start with reduced maintenance costs. As I said, very few drivers are diligent about checking and adjusting air pressures. ATIS does it for them - and for us - so we don't have to worry about it when trailers hit our yard.

"And, as you know, tires last much longer, wear much more slowly and produce more retreadable casings when they're kept at the right inflation pressure all the time.

"With tires being the number two non-payroll cost and the number one maintenance cost, that makes a huge difference."

Are there other benefits?

"There's almost no end to them. Fuel economy is slightly better, because low tires waste fuel. At today's fuel prices, we can't afford to waste any.

"Plus, the system should last the life of the trailer, and when you go to sell the trailer, having ATIS increases its resale value.

"But probably one of the biggest advantages is the reduction in tire failures."

How important is that?

"We deliver very time-sensitive freight. Being late can cost us many thousands of dollars. And while an ATIS system can't prevent you from losing a tire to a chunk of rebar, it can prevent a lot of other losses.

"For example, one of the most common reasons for a tire problem is because it ran 'flat.' Now, it's important to remember that 'flat' doesn't mean completely flat. At 20 percent or more underinflated, the tire is defined as being 'flat.'

"The tire runs incredibly hot, the tread wears much faster, the casing ages much more quickly and in the worst case, the whole thing comes apart on the road."

And that means lost time.

"Not only lost time, which can be very expensive, but lost money as well. If you price a service call, together with a replacement tire, a single lost tire can come very close to the cost of an automatic tire inflation system - for all 8 trailer tires.

"And, with some types of punctures, ATIS can actually keep the tire inflated well enough to get it into the shop for service.

"We once found a 3/8-inch drill bit in one of our tires, but the ATIS system kept the tire at the correct inflation in spite of it."

How long does it take for ATIS to adjust a tire to the proper pressure?

"It depends on how far off the pressure is. We've seen a single tire, if it isn't broken off the bead, go from nearly flat to properly inflated in as little as a mile.

"If a bunch of tires are low, it will take longer, of course. But still, even that's far better than just having the driver run down the road without doing anything."

How many of these systems have you tried?

"Almost all of them. In fact, we have several different ones running right now. We're evaluating them to make sure we've got the one that works best, lasts longest and returns our investment quickest."

Is there a lot of maintenance needed on these systems?

"Nothing is maintenance-free. If it were, people like me would be out of a job. Fortunately, though, the maintenance necessary is very low."

Does the driver have to do anything?

"About the only thing a driver has to do is report trouble. There's an indicator light on the front of the trailer that the driver can see in the rear-view mirror.

"It indicates when the system is putting air into the tires or when there's a problem. It can be a little annoying, we know, because we've heard of drivers removing the bulbs, smashing the lights or covering them with duct tape.

"Still, that indicates it's hard to ignore."

Is ATIS difficult to install?

"Not really. Best way, of course, is to order new trailers with the system already on them, but you can retrofit too.

"Most axles are hollow, and some systems pressurize the axle, while others use a hose that passes through the axle. Generally, the only moving part is a rotary union that connects an inflation hose between the axle and the valve stem.

"That rotary union is probably the most sensitive part, and you need to exercise some care to install it properly, but beyond that, the system we use is pretty low maintenance."

What about ATIS for drive and steer tires?

"The systems that exist for that are pretty expensive, but they're coming down in price. It won't be long before we'll be able to maintain the correct air pressure in every tire. And that will really extend tire life and reduce tire and emergency road service costs.

"We're really looking forward to that."

What do you need next on ATIS?

"The biggest thing we could use right now is for tire dealers and truckstops to realize they're losing revenue by not being prepared to service ATIS systems. We need them to start stocking the parts and training their people how to service them."

Our thanks to Carl Tapp and to the manufacturers of several of today's ATIS systems for their assistance in preparing this article.