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Tire Rating and Tire SafetySpeed Rating
The speed rating, “H” in the diagram, denotes the speed at which a tire is designed to be driven for extended periods of time. You should know that the placement of the rating information has changed over the years. Prior to 1991 they would have appeared on the tire this way:
P212/65HR15 or P212/HR16 95H.
Since 1991 you will see this designation: P212/65R15 95H.
It is important to know that the ratings assume that the tire is not damaged and is not carrying loads that exceed the tires load rating. Even if a tire has been repaired the manufacturer will not guarantee the rating will hold up as they cannot vouch for the quality of such repair(s).
The ratings range from 99 miles per hour (mph) to 186 mph. These ratings are listed below. If the increments seem a bit odd it is because they were first established in kilometers per hour and were later converted to miles per hour. Obviously all tires are rated to handle all United States speed limits and are more than capable of going well beyond them. All manufacturer’s, however recommend against using their tires in excess of any legal speed limits. Below is a table which shows speed ratings and the typical use for each.
M |
81 mph |
130 km/h |
|
N |
87 mph |
140km/h |
Temporary Spare Tires |
P |
93 mph |
150 km/h |
|
Q |
99 mph |
160 km/h |
Studless & Studdable Winter Tires |
R |
106 mph |
170 km/h |
H.D. Light Truck Tires |
S |
112 mph |
180 km/h |
Family Sedans & Vans |
T |
118 mph |
190 km/h |
Family Sedans & Vans |
U |
124 mph |
200 km/h |
Family Sedans & Vans |
H |
130 mph |
210 km/h |
Sport Sedans & Coupes |
V |
149 mph |
240 km/h |
Sport Sedans, Coupes & Sports Cars |
W |
168 mph |
270 km/h |
Exotic Sports Cars |
Y |
186 mph |
300 km/h |
Exotic Sports Cars |
Source: tirerack.com
For all you Autobahn driving types, tires with a maximum speed capability over 149 mph, tire manufacturers sometimes use the letters ZR. For those with a maximum speed capability over 186 mph, tire manufacturers always use the letters ZR.
As vehicle top speeds have continue to go up in recent years speed designations have changed in order for people to better match the tire to the vehicle. For example you will now see the speed rating “Y” closed in parentheses 285/35ZR19 (99Y) if the top speed of tire has been tested in excess of 186 mph. This is done to differentiate that tire from one with a “Y” without the parentheses. This is important because the old “Y” designation may not be suitable for vehicles that can exceed 186 mph.
The most important thing to remember is that when replacing tires you should go with a tire that carries at least the same or better rating of what the manufacturer recommends.
Continue to the tire maximum inflation pressure area by clicking here or select from the sidebar.
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