What does 11r mean in tires?

Q: What does the R mean on a tire?

This is indicated in percentage of the tire width. R” stands for the construction method of the tire indicating the tire is a radial tire. The following two numbers (16) indicate the diameter of the wheel rim in inches. The next two or three numbers (94) indicate the load index of the tire.

Understanding truck tire sizes is important for the safe transport of goods and people. Trucks and buses carry many thousands of pounds, and the tires must be correctly chosen to safely carry the loads. Transmission gearing and road speed are also affected by the tires selected.

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Aspect Ratios
More Articles
What does 11R22 5 tire size mean?
How wide is a 11r 22.5 tire?
What is the difference between 11R22 5 and 11r24 5?
What does the R mean on a tire?

Types

Truck tire sizes follow a standard formula. Standard profile will look like 11R22.5G and low-profile will have the form 275/80R22.5G. The 11 or 275/80 gives the section width and aspect ratio. "R" is for radial tires, bias ply tires will have a dash. The 22.5 is the wheel diameter; the "G" is the load rating. Section width is the widest point of an unloaded tire, and the section height is from the wheel rim to the outside of the tire.

Aspect Ratios

Truck tires sizes starting in 8, 9, 10, 11 and 12 are standard profile tubeless with the tire body width in inches. Standard profile tires have an aspect ratio of 88 percent. The height of the tire from rim to tread will be 88 percent of the width. An 11R22.5 tire will be approximately 11 inches wide and 9.5 inches high. Low profile tires show the width in millimeters and the aspect ratio. A 275/80R22.5 tire is 275 millimeters wide 220 millimeters high. Typical low aspect truck tire ratios are 70 percent, 75 percent and 80 percent. Tube-type tires are given widths as 9.00, 10.00 or 11.00, as in 1000R20, pronounced "ten hundred R twenty." Tires requiring inner tubes have an aspect ratio of 98 percent.

Wheels

The wheel size says a lot about the tire. All wheel sizes are the wheel diameter in inches. Whole number sizes indicate multi-piece wheels that require an inner tube. Most common tube wheel sizes are 20, 22 and 24 inches. Wheels with half-inch sizing are single piece for tubeless tires. Common sizes are 19.5, 22.5 and 24.5 inches. Truck wheels also come in several widths; a tire size chart should be consulted to match the tire size and wheel width.

Load Range

The final letter in the tire size is the load range, which indicates how much weight the tire can carry. The popular load range "G" in 11R22.5 and low-profile 22.5 can support 6,175 lbs. inflated to 105 psi in a single tire application. Tires mounted as duals will have a slightly lower load rating. Also, tires will have different load capacity at different inflation pressures. The tire manufacturer will provide a chart with all of the necessary data. The big load range "L" tires on the front axle of dump trucks and cement mixers can carry loads of over 12,000 lbs. per tire.

History

Modern tubeless, radial truck tires have become the standard on trucks only since the late 1980s. Before then, the most common sizes were 10.00-20 and 10.00-22. The tubeless radial equivalents of these tires are 11R22.5 and 11R24.5. The low-profile tires became common in the late 1990s on highway trucks. Low profile offers less weight and better performance.

References

Writer Bio

Tim Plaehn has been writing financial, investment and trading articles and blogs since 2007. His work has appeared online at Seeking Alpha, Marketwatch.com and various other websites. Plaehn has a bachelor's degree in mathematics from the U.S. Air Force Academy.

A very common question we receive is “How do I know what kind of tire I am running?”
While there are a number of different size truck tires available today, the four most common sizes used are : 295/75R 22.5, 285/75R 24.5, 11R 22.5 and 11R 24.5

11R22.5

Commonly referred to as a “Tall 2”

11R24.5

Commonly referred to as a “Tall 4”

295/75R22.5

Commonly referred to as a “Low Pro 22.5 or Low 2”

285/75R24.5

Commonly referred to as a “Low Pro 24.5 or Low 4”

In order to determine the size you’re running, it’s beneficial to understand
exactly how to read the sidewall of your tire. Check out the tire below.

Move your cursor over the blue markings to learn what each item means.

DOT
The DOT tire identification number indicates compliance with all safety standards established by the U.S. Department of Transportation and provides additional information about the tire. It’s a series of letters and numbers. The last four numbers are the week and year the tire was made.
Load Index
The load index number corresponds to the maximum load-carrying capacity of the tire.
PSI
Recommended Cold Inflated Air Pressure
Diameter
The diameter is the size of the wheel from one side to the other.
Radial
Tires with an “R” indicate radial tire construction
Height
The aspect ratio indicates the dimensional relationship of the section height to the section width
Width
The width indicates the widest point of a tire from sidewall to sidewall.
Speed
Indicates maximum speed at the rated carrying capacity
Ply
Tire ply construction and weight capacity rating

Tire Mount

•Yellow Dot
Indicates the light point of the tire, line the yellow dot up with the heavy point on the wheel which is at the valve stem. This method provides the most balanced assembly.

• Red Dot
Indicates the high point of the tire. The tire can be mounted with the high point (red dot) 180 degrees off from the dimple located on the back side of the wheel’s outer flange which indicates the high point of the wheel. This method provides the most round assembly.

• Green Dot
(or any other colored dots)
Indicates the tire has passed inspection at the assembly plant, these inspection dots have no useful meaning for mounting.

What does 11R22 5 tire size mean?

For instance, a 11R22. 5 is a standard aspect ratio tire. 11 is the nominal tread width measured in inches. R is for radial, and 22.5 is the wheel diameter measured in inches. The aspect ratio by default is about 90 which means that the tire sidewall width is 90% the width of the tread.

How wide is a 11r 22.5 tire?

Sizes & weights.

What is the difference between 11R22 5 and 11r24 5?

The maximum single load of 11R22. 5 tires is 6175 lbs, and their inflation pressure is 105 psi. 11r24. 5 tires can handle a maximum single load of 6610 lbs, and their inflation pressure is 105 psi.

What does the R mean on a tire?

This is indicated in percentage of the tire width. “R” stands for the construction method of the tire indicating the tire is a radial tire. The following two numbers (16) indicate the diameter of the wheel rim in inches. The next two or three numbers (94) indicate the load index of the tire.