A Balancing Act

May 21, 2007
Wheel-service equipment makes easy work of advanced vehicles.

The telltale signs of unbalanced wheels are easy to catch: vibration in the floorboard or steering wheel at highway speeds, and scalloped or cupped wear patterns on the tire. An unbalanced tire usually means one section of the tire is heavier than others. One ounce of imbalance on a front tire is enough to cause a noticeable vibration in the steering wheel at about 60mph.

But for a busy tech, going from perilous shakes to that new-car ride isn't always a smooth transition, especially given the new complexities of tires and cars in general. Newer, more sophisticated car models are demanding a more complex market of high-tech, and oftentimes more expensive, wheel-balancing equipment.

Diagnosing the shakes

From price to features to training, there are a whole lot of issues involved when selecting, and selling, wheel balancing equipment.

"Reliability and accuracy are interchangeable when selecting this equipment," said Bob Surey, TeamBear USA national sales manager. "And I would also add to that life expectancy. Customers get very frustrated when they have a 5- or 6-year-old balancer and they're told that the parts are no longer available."

More high-end machines measure an array of vibration-related issues, and troubleshoot more than the balancing alone. In most instances of unwanted gyrations, balancing is only part of the problem.

"Companies do more than balance on the assembly line," said David Scribner, product manager for Hunter Engineering. "They are measuring eccentricities … they're measuring radial force, non-uniformities. Tires, in fact, are being match-mounted/assembled by outside contractors at outside plants."

Kevin Keefe, director of marketing at Hennessy Industries, also notices big issues going on from the tire and wheel side, as OEMs have expanded options and continue to introduce more wheel designs to the market.

"A lot of times the root of the problem isn't so much the balancer," Keefe said. "Shafts and cones are usually good for three years or 30,000 cycles. A 10 inch diameter wheel nick will cause 8 ounces of error, and the balancer will show zero.

roblems like these will bring a lot of vehicles back. Consider mounting accessories, not just balancers. Most aftermarket wheels are more eccentric — distributors and salesmen must educate end-users."

From the industry standpoint, that means a big shift for wheel service equipment to do more than balancing. The equipment also needs to have the right features and accessories. It needs to maximize ride-feel.

"Wheel balancers used properly will solve the majority of issues," Scribner said.

A multitasking machine

Vehicles are changing. Car companies are giving consumers more sensitive vehicles. So the expectations of the equipment must also evolve. This can be seen in vehicles that are being built with lighter and fewer suspension components, thus changing things like tire construction.

"A good example is the spring rate tension," Scribner said. "Look at the Ford F-150. The tires today look identical to how they looked 15 years ago. But now they have a much higher spring rate. They were 1,000 pounds per square in compressor rate. They're now 2,000. Because the rate has doubled, any irregularities, any non-uniformities, are greatly magnified.

Chassis are also more sensitive and rigid. Non-balancer related forces have the same symptoms as wheels that are out of balance. Any slight error can lead to balancing issues."

Another factor that can affect wheel balance is wheel weight problems. Newer products are performing better balances with less weight. Scribner noted that the average shop spends about $10,000 per year on lead, and the cost of lead is going up.

"Once you get past mounting errors, which are huge, the next issue is usually wheel weight problems," Keefe said. "This often occurs when weights are pulled off of one vehicle and applied to another, leading to problems like static issues, noise-level or out-of-round, where the tires and wheel assembly are not perfectly round. You can balance a brick, but it's not going to roll."

Heating up the industry

Wheel-balance companies are constantly involved in a game of technology keep-up as cars become more complicated. One example of this is in the readout display. Where these machines used to have LEDs giving a readout, they now use LCD displays. The bottom line is that balance features have gotten so prolific, to rely on a number readout screen isn't a good investment.

"The cost of LCDs (basically computer monitors) are coming down so fast," Scribner said. "Also, the generation of operators is so different … guys in garages now grew up playing video games and are more comfortable with it [LCD technology]."

Another technological advancement in use is sonar.

"Sonar measures wheel width automatically without operator input, and measures radial eccentricity (runout) without [user] contact to give the most accurate balance," said Surey. "It gives an accuracy reading within 1 gram."

Surey expects sonar technology to become more affordable as volume increases and new wheels and suspension systems continue to be enhanced.

Newer machines are relying on the techs less and less to manually enter information such as width, diameter and the type of wheel weight they want to use. Now all of this can be accomplished by simply picking up the arm, or putting it down, and touching it to the weight position. Accuracy has also greatly increased. Newer machines have practically all measurements and balance modes.

A pretty penny

There's often no standardization between car companies on the tooling required when end-users spend a smaller amount of money on a balancer. Going for discount can then result in limited universal tooling that doesn't work today on many types of cars.

"You've got to realize the range of choices is mind-boggling," said Scribner. "You can buy [this equipment] on the internet with a credit card from no-name offshore commodity-type equipment dealers for less than $1,500. At the high end of the market you can spend upwards of $20,000. It's important for people to have an understanding of what they want to invest in."

According to Scribner, about 20,000 garages in the United States utilize high-end machines, which he cites as being able to solve problems before they happen and increase customer satisfaction.

Show, tell and sell

"Years ago, you could sell balancing machines to customers and walk away knowing he'll have the equipment he needs to do his job," Keefe said. "Today, because of sophisticated vehicles more prone to vibrations, you need to offer a balancing solution rather than a piece of equipment."

Techs are finding they need more today in terms of adaptors and accessories than they did five years ago, Keefe explained. And wheel-service equipment companies comply by offering standard packages that cover most original equipment vehicles. Extended packages go one step further to include aftermarket wheels and light trucks, while premium packages cater to larger systems such as medium-duty truck applications.

Garages are finding out about the complexity of tires and balancing equipment.

"High-end balancers also measure radial and lateral forces," Scribner said. "They're more exact, and in the long run they are much cheaper than anything that will do the same job. It's very cost-efficient. It's something a garage cannot afford to not have."

For a shop owner, a little show and tell about current wheel service trends pays big. This is one opportunity for everybody to make an income that wasn't there before.

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