AKRON (Jan. 17, 2005) — Progressive tire dealers should embrace state-of-the-art tire pressure gauges. Simply put, it's time to take air pressure measurement as seriously as wheel nut torque.
Good dealers don't guess at wheel nut tightness anymore. Nor do they assume that an otherwise-reliable air wrench will automatically deliver the desired torque. Instead, they measure lug nut tightness with the proper measuring tool: an accurate torque wrench. Upgrading their wheel-installation procedure amounted to a relatively modest investment in time and tools.
But this improved procedure also meant a monumental increase in professionalism as well as a front-line defense against lawsuits over loose wheels.
Similarly, advancing technology and the ever-present threat of lawsuits should motivate dealers to invest in durable, highly accurate, self-calibrating tire pressure gauges. At the same time, dealers should create and implement a standardized form on which technicians routinely record all air pressure readings. One copy of this form should go with the customer's paperwork; another should go into the dealer's files.
During the Automotive Aftermarket Industry Week trade shows last November in Las Vegas, a colleague showed me Waekon Corp.'s T2005 Deluxe Tire Pressure Gauge. Yes, I've used Waekon test equipment many times to perform pressure tests on various vehicle systems. However, hustling the name of a well-known company isn't my objective here.
Rather, I cite Waekon's T2005 gauge as a prime example of the accuracy and professionalism we should bring to tire pressure measurement today. Remember, a basic sport-utility vehicle now costs $30,000. Potential lawsuits lurk around the corner. These conditions tell me it's time we finally retire those inaccurate, unreliable pocket gauges.
First of all, consider that both DaimlerChrysler A.G. and General Motors Corp. service engineers thought enough of the T2005 to offer it in their dealership tool/equipment programs. That alone should remind tire dealers about the importance of accurate tire pressure measurements.
Second, this 100-psi gauge is accurate to plus or minus 1 percent of its operating range. I'll use convenient, round numbers to put this into perspective for you. Suppose the spec is 30 psi and you finalize the tire pressure using this T2005 digital gauge. If so, you know the actual pressure is between 29.70 to 30.30 psi when the vehicle leaves your bay. In my book, that's pretty darn accurate.
What's more, the digital readout is faster and easier to use than the traditional analog (needle-type) gauge. With digital, what you see is what you get, regardless of the angle from which you're viewing the gauge. It's also much more consistent than analog because there's no estimating or guesswork involved. Surely, you've heard the estimating that occurs: “Hmmm, the needle is kind of closer to 31, so the pressure's somewhere on the high side of 30 psi. But if I thump the gauge on my knee first, I get 33, so I'm probably averaging about 32 here.”
There was a time when digital displays on diagnostic shop equipment were perceived as being weak and/or prone to failure. But, among others, Waekon's been building digital-display automotive pressure gauges for many years now. These products have earned a solid reputation for withstanding the bumps and bruises common in the auto repair environment. The countless technicians I know who use these gauges agree that they hold up and stay in calibration very well.
Third, a modern gauge like this one enhances accuracy and consistency by automatically calibrating itself when you turn it on. This means it zeroes itself as well as compensates for ambient air temperature and atmospheric pressure. In fact, its circuitry constantly compensates for temperature and altitude while you're using the gauge.
(By the way, when was the last time you had the accuracy of any of your tire pressure gauges checked by a qualified specialist?)
It's likely that most Tire Business readers have been brow beaten about the impact of temperature and altitude on tire pressure. You can't control when customers ask you to check inflation for them (hot or cold tires), but at least you needn't second-guess the gauge's accuracy under any working conditions.
Fourth, Waekon includes a document certifying that the accuracy of the T2005 is traceable to National Institute of Standards and Technology (NIST) standards. Look it up on the Internet or ask your engineer pal about NIST-traceable standards. The difference between using this digital gauge and a pocket gauge is like the difference between measuring something with a yardstick and a micrometer.
For your information, Waekon does recommend returning the gauge annually for an official calibration check against its own NIST-traceable instruments. There's a $49.95 fee for this calibration check.
The T2005 digital tire gauge lists for $350. To me, cost-justifying an upgrade from pocket gauges to space-age instruments is easy. Suppose you buy four of these digital gauges at a modest discount of 50 bucks apiece. That's four times $300 for an initial investment of $1,200.
Now suppose your tire store sells at least two complete sets of tires per day, five days per week. That's eight tires per day times five days or 40 tires per week. Suppose your business is open 50 weeks per year. Forty “doughnuts” per week times 50 weeks is 2,000 tires per year. What if you wanted to pay for those digital tire gauges within a year? The $1,200 investment divided by 2,000 tires per year means you'd have to increase the average price of a tire by $.60.
In other words, that's six dimes per tire for bragging rights to having the most accurate gauges in the neighborhood. Promote that accuracy to the safety-minded soccer moms in their minivans. Promote the accuracy to the executive who's driving the Jaguar or the BMW. Odds are the dealer who sold him the car doesn't have gauges as good as yours!
Promote that accuracy to the younger set that brings import “tuner specials” to you for high-dollar, 16- and 17-inch fitments. Promote that accuracy to Mother Superior when she's buying new tires for the van she uses to shuttle kids to and from church activities.
Instead of apologizing for the investment in modern gauges, market their accuracy as a value-added feature provided by the most-conscientious tire store in town. If you do nothing else or say nothing else, attach the tire-pressure sheet to each invoice. The sheet should show a simple photograph of your fancy pressure gauge with the NIST-traceable accuracy as well as the actual tire pressures recorded that day on the customer's vehicle.
Upgraded image helps
What if the unthinkable happens? What if someone tries to attribute a vehicle crash to shoddy or careless workmanship at your tire store? Which technique do you think will enhance your overall image to an accident investigator, judge or jury—a ratty old pocket gauge or a modern gauge with NIST-traceable accuracy?
Furthermore, think of the impression the tire pressure chart could make. On a routine rotation, for example, it would emphasize that you're concerned enough to record existing as well as “corrected” tire pressure. An additional, say, two minutes per car for this paperwork could yield massive “image dividends” for your business.
Using the modern gauge and re-cording the pressures are just another example of exceeding expectations in a very competitive marketplace.
Last but not least, the onslaught of tire-pressure monitoring systems mandated by the Transportation Re-call Enhancement, Accountability and Documentation (TREAD) Act doesn't excuse you from checking and correcting air pressure accurately. For example, don't assume that all the dashboard warning systems display actual pressure at each tire. You may need special equipment or an appropriate scan tool to get that information.
When all's said and done, the fastest and most-accurate way to verify tire pressure is with an independent and accurate measuring device such as a modern digital gauge. To me, verifying tire pressure first is the most-logical beginning to any diagnosis of a tire pressure monitoring system.
Starting to sound like the more things have changed, the more they've remained the same, huh?
The lower-cost-pressure-monitoring systems sense changes in tire pressure indirectly. They do this by monitoring wheel speed via the anti-lock brake system (ABS) wheel speed sensors. You see, when tire pressure changes, the tire's rolling circumference—and therefore, its speed—also changes. But monitoring systems that use this indirect measurement method can't distinguish which tire is low. They turn on the warning light and you're supposed to pinpoint the low tire the old-fashioned way, with a tire-pressure gauge.
What's more, experience is showing that these indirect systems are prone to false alarms due to conditions such as slippage on wet roads, snow or ice!
On other systems, the tire-pressure warning light comes on when the pressure in one or more tires goes above or below a specified pressure. The minimum and maximum pressures beyond which the warning light comes on are 15 psi apart from each other. But the quickest, accurate way to begin troubleshooting the problem is still checking tire pressure with a good gauge.
Before I wrap up, a few more numbers may help your perspective. For instance, experience shows that a tire that's 3 to 5 psi below specification may turn on the warning light on some pressure monitoring systems. The old rule of thumb is that tire pressure changes 1 psi for every 10-degree F change in temperature. That may not sound like a big deal. But experience is suggesting that temperature changes may be causing false alarms on some of the tire pressure monitoring systems. Technicians report that the first line of defense still begins with setting tire pressure to spec with an accurate gauge when the tires are cold.
Continental A.G.'s Continental Teves unit has developed a high-end pressure monitoring system that can sense tire pressure changes as small as .10 BAR or 1.50 psi. Would you want to diagnose this system with the help of a pocket gauge—or with a modern gauge with a resolution of .10 psi and NIST-traceable accuracy?
Long-term, I'm convinced that more accurate pressure gauges will became a staple in our business. Smart tire dealers will realize what a simple, fast and effective troubleshooting tool they are. Savvy dealers also will see they're a potential marketing tool, too.