Ever notice that your tire is covered with writing? It's like some hieroglyphic art form. Of course, Novi drivers know that it's not just graffiti, but to most of us, it might as well be. Would you like to know what all those codes on your tire mean? It won't lead you to buried treasure, but it could help you make a better tire purchase at your local Novi tire store.

Prominently featured on your tire is a set of numbers and letters that looks something like this: 225 50 R 16 92 H. The first number is the width of the tire in millimeters, or the width between the sidewalls of the tire when it is fully inflated and not carrying a load. When Novi drivers replace tires, they need to match this width number, or the tires won't fit properly in the wheel wells.

The 50 is the aspect ratio of the tire, which is measured by taking the height of the sidewalls and dividing it by the tread width. If you drive off-road around the Novi area, it should have a high aspect ratio. For high performance on the road, you want a lower aspect ratio.

The R simply means this is a radial tire.

The 92 is the load rating index, or in other words, a rating of how much load a tire can safely carry. If you frequently haul heavy loads around Novi, you will want a tire with a high load rating.

The last letter in our “code” sequence is the speed rating on the tire. Not all tires have this rating. In general, the closer the letter is to the end of the alphabet, the higher the speed rating. In other words, Z is the highest rating and A is the lowest. One exception: H comes between U and V. Why? Your guess is as good as mine.

If you'd just as soon ignore all of the markings on your tire, that's okay. When you need to replace your tires just ask your friendly and knowledgeable Sovel's Auto Service tire professional for his auto advice on the best tires for you and your vehicle. Replacing tires is a standard part of preventive maintenance for Novi drivers vehicles. We all have to do it sooner or later. And the better we understand what we're buying, the better our vehicle will perform and the safer we will be on Michigan roads. Good vehicle care is informed vehicle care.

Sovel's Auto Service
41425 W. 10 Mile Rd.
Novi, Michigan 48375
248-348-7337