By the Numbers: Tire Replacement at Auto Lab Livonia in Livonia
May 22, 2017
Ever notice that your tire is covered with writing? It's like some hieroglyphic art form. Of course, Livonia 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 Livonia 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 Livonia 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 Livonia 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 Livonia, 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 Auto Lab Livonia 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 Livonia 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 MI roads. Good vehicle care is informed vehicle care.
Auto Lab Livonia
36251 Five Miles Rd
Livonia, MI 48154
734-432-6000
http://www.autolablivonia.com
Need Service?
More articles from Auto Lab Livonia

Lubricate Driveshaft
April 20, 2025
See if any of these are happening to your vehicle. You feel it vibrating excessively underneath when its running, or you hear strange clunking, grating, or grinding sounds coming from beneath. Maybe its hard to turn your vehicle, or you can hear squeaking when youre going slow. Perhaps you fee... More

Rubber Match (Tire Replacement)
April 13, 2025
A set of new tires isn't probably high on anyone's list of exciting purchases. But since your life is literally riding on them, it's probably a good idea to know when it's time for you to buy new ones. If you've been feeling your vehicle slipping more in wet weather or it takes a longer distance... More

Differential Essential (Differential Fluid Exchange)
April 6, 2025
What's the dif? To an automotive technician, it's the differential, a part of your vehicle that helps direct power from the engine to the wheels. The differential is a gearbox that enables the drive wheels to turn at different speeds (they do that when you turn). Inside the differential is a f... More