Brushing up on their truck tire technology skills. This past February, a group of customers from the Northeast Region trekked to Fort Stockton, Texas to visit Bridgestone's Texas Proving Ground (TPG) to experience tire testing first-hand.

During two days of technical seminars, classroom and round table discussions, together with "On Track" demonstrations, they gained a deeper appreciation of the importance of tire testing, and an opportunity to interact with each other and Bridgestone field engineering personnel.

The participants found the program well worthwhile, and we think, so will you.

"When you can feel, touch and see, you really learn.
I'd recommend it to anybody." --John Joseph, Old DominionTruck Leasing

Where is the Bridgestone Texas Proving Ground?

About 12 miles west of Fort Stockton, Texas, just off highway 10. That's about 231 miles from El Paso and about 240 from San Antonio, roughly midway between them.

Why such a remote place?

Land and weather, mostly. TPG occupies over 6,000 acres, a square piece of land roughly 3 miles on each side. It's relatively flat and ideal for all kinds of test tracks.
And, the climate is pretty mild. Annual rainfall averages 12 inches. The average temperature is 67 degrees, it's not very windy, and the sun usually shines 360 days a year.
The result is that roads last a long time, and test conditions are ideal nearly all year round.

Why bring customers out there?

Because it's a unique opportunity for Bridgestone users to pick up some first-hand information and know-how, observe the complexity of tire testing, and see things they'd likely never see at home.

For example?

A real demonstration of SAE J1376 fuel economy testing, for one thing. TPG's 7.7 mile oval track is nearly ideal for fuel economy tests: no stop signs, no traffic congestion, and all one-way roads.
Participants observed as two nearly identical trucks were fitted with removable fuel tanks, so that after making time and speed controlled laps around the track, the tanks could be weighed to precisely determine how much fuel had been consumed.
They also learned what kinds of things can "scrub" a test, including winds over 15 mph, rain, too much deviation in lap times by drivers - even a single missed gear change.

What subjects are covered?

Bridgestone field engineering personnel select a series of topics, tailored to the needs of fleets they've invited. There are literally dozens of different subjects to choose from, including tire technology, maintenance ideas and tire life cycle cost analysis. The result is that each seminar is a unique blend of classroom presentations and on-track demonstrations.

What's this about customers getting to drive vehicles?

In a couple of cases, after Bridgestone test drivers finish demonstrating things like wet stopping distance and wet lateral traction, customers with valid CDLs are invited to drive the trucks themselves.
Wet stopping is particularly popular. A long skid pad is flooded with water, and bobtail tractors with drive axle brakes disabled drive onto the wet pad at about 30 mph.
Drivers are instructed to lock the brakes, and skid to a stop. Stopping distance is measured using a set of Bridgestone R227 steer radials, then customers can switch to an identical tractor with different steer radials and try the test again.

And wet lateral traction?

This test is done on a circular track, half of which is flooded with water. The idea is to go around at faster and faster speeds, until you feel the tractor starting to slip sideways. Again, customers are invited to try driving the truck themselves - to feel the effect.

What does all this prove?

Customers aren't trained test drivers, and while the whole seminar takes less than two days, a single test, like a fuel economy test, can take days or even weeks to complete.
The idea is to give participants some technical background, some helpful information, a feel for testing and a sense of the many variables involved.

How about tire torture tests?

There are several. For example, the group from the northeast watched a couple of tires being dragged over one of the most treacherous sets of curbstones you can imagine.
A special, offset trailer allows two tires, one with and one without a decoupling groove, to run up and down over a set of zig-zag curbs.
In just a few passes, participants see that tires with decoupling grooves can experience severe rib tear, while those with a solid shoulder seem to hold up better.
There's even a special test area that shows how a single encounter with a typical curb can permanently damage a tire.

What's the most impressive?

So far, it's probably "instant air loss." In this demonstration, a truck is driven at 60 mph, and one steer tire is suddenly gouged by a wicked-looking steel blade.
Air loss is virtually instantaneous, but as numerous groups have observed, the TPG test driver is able to maintain vehicle control and bring the truck to a safe stop a few hundred feet down the track.

Do customers get to drive on this test?

Afraid not, but one lucky participant gets to ride with the TPG driver, and experience the test from inside the cab.

Are there other tests customers can see?

Absolutely. The TPG staff and Bridgestone field engineering personnel can also show how "Peak & Slide" braking tests are done, what happens with severe toe angle misadjustment (see "What in the World?" in Real Answers, Vol. 3, Issue 1, page 34.), and TPG visitors can even go underground for a "road's-eye view" of wet traction.

How is that done?

TPG technicians drive a test truck over a 4-inch thick piece of glass mounted in the wet traction test surface, while seminar participants stand in a room below, and look up through the glass. You've got to be quick, but you can get a feel for how those wet glass plate photos are made, and how different tread designs produce different wet traction characteristics.

How can we get to go to one of these seminars?

Ask your Bridgestone representative. To provide individual attention, seminar size is very limited. And, because Bridgestone's TPG is a working test facility with lots to do, only a few of these seminars can be scheduled each year. It's a great way to learn more about the technology that goes into the tires you use every day.

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