Mystifying Math: Addition to Tire Sidewalls Leaves Consumers Confused - Tire Review Magazine

Mystifying Math: Addition to Tire Sidewalls Leaves Consumers Confused

When we bend over to read a tire sidewall, we practically need a magnifying glass to read all the information, especially on super low aspect ratio tires. Why is this? It seems we’ve added – and will continue to add – more and more tire nomenclature, all of it designed to save us from ourselves.

Despite every raised black sidewall letter or number put there to save our souls, most drivers pay little or no attention. Frankly, there is so much there it’s like reading the fine print on a tire warranty card. No matter, as the industry globalizes and sizing and designs become more universal, the race (or need) to add more tire sidewall warnings is in full swing and it appears there is no end in sight.

UTQG grading is already part of the sidewall landscape, even though most consumers couldn’t begin to explain what it means. Next will be some grade level for a tire’s rolling resistance. And now there are those who want to brand the tire’s failure date – or end of life expectation – on the sidewall.

At best, this is an insane legal shuffle given the variables inherent in the daily use of a tire: driver habits, road conditions, vehicle type – you know the list, and it’s lengthy.

Now to the heart of this column, which is how to get rid of some of the scribbles on a tire sidewall, rather than adding more. What’s wrong with a little subtraction?

Addition Woes
Carmakers continue their horsepower race (addition), tiremakers continue to build higher and higher speed-rated tires (addition), brake makers continue to build super brakes to bring these beasts to a stop (addition) and the price of fuel at the pump is going up. Some say it may not stop at $6 a gallon (addition), and we’re not building very many fuel-efficient vehicles in the U.S.

Detroit gives us 500, 600 and even 700 horsepower gas guzzlers at a time when they need to build a 150 horsepower vehicle that can squeeze every ounce of fuel and power out of a small block V4 engine. True, there are a few out there, but they lack refinement.

It seems the entire automotive industry is focused on addition. So where is the subtraction?
Let’s return to the tire sidewall. Here’s what we really need: First, tire size and diameter, that’s an imperative. And they should be easy to find and read. The load index is equally important. But we are beginning to doubt the necessity of a speed rating designation.

When you really think about it, nearly every consumer tire produced today has a speed rating. The real difference comes with UHP tires – W, Y and Z rated rubber. Once upon a time, we included speed rating designation as part of the tire size; maybe we can save some space and go back to that method.

For all of the complaints we get about it being some secret code, do we really need a DOT designation? Especially when you consider that the technology already exists to put RFID tags in tires, which would carry the “born on” date and location. Think about the savings in mold changes alone.

Here’s another vote for RFID tags: While it’s true that there are good tires coming out of southeast Asia and other parts of the world, it is also true that counterfeit and copycat tires are also making their way into this country. So why don’t we simply subtract the DOT designation from a sidewall and go with the more foolproof RFID tag? After all, it does no good to the tire buyer or dealer who has no idea if a tire is the real deal or just a fake.

Can We Have It All?
Any tire buyer is faced with a bewildering array of tire sizes and types from which to choose, not to mention the number of greenbacks he is going to have to slap on the counter. Is it possible to ever reach a point when a tire sidewall will be branded so completely that it will remove every question in the tire buyer’s mind? Answer: No!

Let’s look at tire grading for a moment. Have you ever seen a customer get down on one knee with a flashlight so he can read the UTQG ratings? Again, the answer is no. Today’s tire buyer is looking to the tire dealer to tell him what those grades mean, what speed ratings mean, as well as construction, inflation pressure and on and on.

Here’s another: Today, virtually 100% of all passenger and light truck/SUV tires are radials. You’d have to look long and hard to find a bias tire for anything other than a classic car. Still, we are required to stamp “Radial” on the sidewall. Isn’t that like stamping “Tire” there?

So why do we continue to do the same thing and expect different results? Some of it is a matter of convenience, some a matter of convention and the rest because of product liability attorneys. Most people don’t have a clue what is branded on their sidewall – other than size, maybe – but now tires have to carry multiple warnings to help avoid costly legal action.

Back to Basics
Back in the day, I washed my car nearly every day and hand-lettered my black sidewall nomenclature with white rubber paint. I took particular interest in the size and inflation pressure. A visual inspection of tire wear patterns always followed and that was the extent of what I needed to know. Today I have information overload on my sidewall and if that weren’t bad enough, just look at what the tire designers have devised.

Raised white letters, raised white outline letters, raised black letters, serrated letters including the brand name and artwork designed to make the tire a piece of rolling art. And that’s great; we should take pride in our products.

Looming even more important in our litigious days is the  the DOT code. The greatest use of the DOT code comes in the event of a recall. That function can be replaced by a simple RFID tag. Based on what happens in the near future, adding clear “born on” dates to tire sidewalls may soon be required, despite the RMA’s protests that tire age has nothing to do with tire safety. After recent “news” reports, that horse appears to have left the barn.

Over the last few decades we’ve been asked (required) by NHTSA to brand bits and pieces of convoluted information. There is so much there now that it is nearly impossible to find the important stuff – like the size.

Do we really need special artwork for M+S and winter ratings? Can’t we work that into the size nomenclature? What about the microprint explaining maximum inflation pressure? What about a simple “Inflate to no more than 45 psi?” which takes up less room and is easier to see – especially on a 35-series tire.

In the interest of cleaning up the sidewall, why not provide a brochure for every tire sold and give it to the tire buyer? They are more likely to read something printed clearly on paper than a bunch of raised black lettering on a tire. Again, it’s a matter of addition vs. subtraction, of common sense vs. no sense.

The body contortions a driver must endure to locate important information on a tire would aggravate anyone. Wouldn’t it make more sense if that information could be comfortably read in the passenger compartment, particularly if the driver is stuck on the side of the road and needs to call someone when they have a tire problem? It is far easier to do that than fumble with a cell phone while trying to read a too-busy tire sidewall parked next to a busy freeway.

We would love to see subtraction replace addition. Let’s use common sense by giving the motorist every reason to stay inside of his vehicle, safe and sound, until we can reach him and give him the help he needs.

In the meantime, keep your eye on RFID technology. It’s a likely candidate for a good answer to the alphabet soup mess we’re muddling through now.

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