If you’re in the market for new
tires, one of the first things you’ll need to do is identify the correct tire
size for your car. In fact, choosing the wrong tires for your car could impact
optimal vehicle performance and safety. Fortunately, it’s rather simple to
identify what tire size you need. Your car’s original tire size can be found in
the owner’s manual but you can also check your current tire’s sidewall. The
sidewalls of your tires provide information about your tires dimensions, load
index and operational purpose.
The markings on your tires can be
broken down to understand your tires size and features.
Let’s break a popular passenger tire
size down to find out what those letters and numbers mean:
The “P” stands for passenger so these tires are often called P-Metric.
Other letters you might see in this area include:
LT: Light Truck
ST: Special Trailer
T: Temporary (spare tire)
NO letter at the beginning of the size description indicates that the tire is Euro-Metric. The biggest difference in a Euro-Metric tire is the difference in load carrying capacities.
“235” represents the width of the tire from sidewall to sidewall. The larger the number, the wider the tire
“70” is the aspect ratio. This is the official sidewall height shown as a percentage of section width. So the sidewall height on this tire is 70% of 235 or about 164.5 millimeters
“R” is the radial construction. This is the industry standard for passenger car and truck tires
“16” means this tire is designed to fit on a rim with a 16 inch diameter
This number is important if you plan on upgrading your wheel size. If your wheel diameter changes, you’ll have to purchase a new set of tires that match the new diameter
“90” is the tires load index. It is a measurement of how much weight each tire can support. “90” indicates a maximum weight of 1,323 pounds per tire. Be sure you multiple your load carrying capacity by 4 to get the total capacity for a complete set of tires
This number can vary but each number can be found on the Load Carrying Capacity Per Tire Chart below.
“H” measures the speed rating. “H” signifies that this tire can safely drive up to 130 mph for an extended amount of time.
Again, this value along with the associated definition can vary so please consult the Speed Rating Chart below.
As you know, there are many other values on a tire. One such value is the DOT code. This particular code helps you determine the age of a tire. To learn more on how to determine your tire’s age, please visit: How Do You Tell The Age Of A Tire?
We hope you find this information helpful. If you need any assistance or have questions about your tire size, we welcome you to call 855-425-3677 for help.