What Do Tire Numbers Mean?

Have you ever noticed the combination of numbers found on the sidewall of your tires? If so, you have likely asked the question, “What do tire numbers mean?” The numbers let you know the size of the tire, the kind of tire, and what it is designed to do in terms of performance. Suntrup Automotive Group would be glad to explain what the numbers on tires mean, which can come in handy the next time you need to purchase a new set in the Fenton area.

An Explanation of What Tire Numbers Mean

The letters and numbers that are part of a tire’s code inform St. Louis drivers of a few things:

• Size
• Load Index
• Speed rating
• Type of Tire Your Vehicle Requires

Here is a code we can use for an example: P215/65R15 95H

Each section of code represents a piece of information to correctly identify the type of tire it is.

• The “P” stands for “P-Metric tire,” which designates that it is for a passenger vehicle. If you see “LT” on your tires, the tire is for a “light truck.” What if there are no letters at the beginning of the code? That lets you know that it is a European style tire, or a Euro-Metric tire. The load capacities of these tires vary.

• Following the “P” is the “215” number, which stands for tire width in millimeters from sidewall to sidewall. In the case of the example above, the width of the tire is 215 millimeters.

• After the forward-slash comes the aspect ratio code. For the purpose of this example, the number is “65.” The ratio of a tire indicates its cross-section to its width. In the example above, the tire has an aspect ratio where its height is equal to 65% of the width. As the aspect ratio increases, so does the size of the sidewall.

• The “R” indicates the tire’s construction. R stands for radial.

• “15” indicates the wheel size from one end to the other. The purpose of this number is to let St. Louis drivers know the size of the tire that can fit on the wheel. For the example above, a 15-inch wheel is required.

• The last part of the example code is “95H.” This number tells you the load index and speed rating for the tire. The load index (“95” in this instance) indicates how much weight the tire can support if the tire is inflated to the proper level. For passenger cars, this number will fall somewhere between 75 and 105. “H” indicates the speed rating. The speed rating is how quickly the tire can safely go depending on the load capacity. This rating is ranked from A-Z. What does the “H” rating mean in the example? This tire can hit a max speed of 130 mph.

Trust the Service Experts at Suntrup Automotive Group

When your vehicle is in need of new tires or other routine maintenance, turn to the professionals at Suntrup Automotive Group. We would love to help get your vehicle back on the roads of St. Charles and running like new. Contact us for more information.