What Does Tire Size Mean

7 Parts Of Tire Size

Your Tire size tells you a lot of information with the fewest amount of characters.  This helps you in the vent that you need new tires, decide that you want to go to something bigger, or are just curious.  

This simple guide will show you what they all mean.  

For these examples we will use the tire size shown in picture:  P225/70R16 91S. . 
VEHICLE TYPE
P225/70R16 91S. . 

This section of the tire size lets you know what the intended use of the tire is.  P for Passenger Tire, LT means Light Truck, ST or T is for Special Trailer or Trailer.  Donut spares or emergency spare tires are often T's.
Tire Width
P225/70R16 91S.

The first set of numbers tells you how wide the tire is.  This is measured in millimeters.  So this tire is 225 millimeters which is about 8.85 inches.  
Aspect Ratio
P225/70R16 91S

This is the size of the sidewall, or the height of the tire between the rim and the outer edge of the tire.  This is a ratio, not a measurement.  So it is actually a percentage of the Tire Width.  So this is 70% of the 225 millimeters or 157.5 mm. (about 6.2 inches)
Construction Type
P225/70R16 91S

This tells you how the tire is built.  Most that you will see are Radial tires (R).  These have a better grip of the road, better fuel efficiency, provide a better ride and are made from layers of strong cords (made of polyester, steel and fabric) that are laid perpendicular to the road.  There are other Construction Types such as Diagonal (D) and Bias (B) 
Wheel Diameter
P225/70R16 91S

This is almost always a two digit number that tells you the width of the rim or wheel, in inches, it will fit.  The rim/wheel is measured from tire bead seat (where the tire sits on the rim) across the width of the tire to the other bead seat.  
Load Index
P225/70R16 91S

The Load index is really not important to most drivers, however, it indicates how much load capacity a tire has when the tire is inflated to the maximum load capacity.  Want to know more?  Read on here.  
Speed Rating
P225/70R16 91S

The way a tire is designed, plays a big part in how it can handle and perform at higher speeds.  As tires travel at higher rates of speed, they become hotter.  Driving faster than a tire can handle can cause loss of traction.  They also wear out faster and in extreme abuse can cause tires to blow..  Read more about speed rating.
Still have questions?  Ask the Tire experts at Beardmore.  You can contact us, use our handy tire tool, or give us a call.  

Beardmore Hyundai proudly serves the Omaha Nebraska area and we are the top choice for your Hyundai Tire and Service needs.  

Contact

Beardmore Hyundai

1203 Fort Crook Road N
Location Bellevue, NE 68005