Having the correct semi-truck or 18-wheeler tire size is vital in the operation of any size fleet of trucks. Properly operating tires impact the bottom line regarding the amount of time the trucks can be on the road and the safety of your operators and others on the road. Having the wrong semi-truck tire size can mean that general wear and tear happens faster. The size matters when understanding how the placement of each tire. More maintenance or less time on the road means your payload is not being delivered.
Over the last few years, the most common truck tire sizes include but are not limited to 295/75R22.5, 275/70R22.5, and 225/70R19.5. While these cover average truck tire sizes and the list is good information to have, it is not ultimately helpful if you don’t understand what these numbers mean to you and your truck/s.
If we take that first size, 295/75R22.5 and explain how semi-truck tires are sized, those numbers break down into several informative categories.
Tire Width - The first number in the series denotes the tire width. Semi-truck tire width can be displayed in terms of inches or millimeters. In this case, a 295-inch wide tire would be massive, so a quick assumption can be made that this is a millimeter marking. Having the correct semi tire width is vital as it is literally where the rubber meets the road.
Aspect Ratio - The second notation (75) after the slash mark is the aspect ratio. It represents the percentage of the length of height to width. This number is an important sizing calculation in tire fitting, and along with rim diameter will help you determine your best tire and wheel combinations.
Tire Construction Type - In this example, the letter R stands for radial (this notates that the steel belts inside are running 90-degrees from the direction the tire is facing). If you see a dash, then the tire is bias-ply (this notates that the nylon belts running anywhere from 30 to 45-degrees from the direction the tire is facing).
Much less common are B for bias belt and D for diagonal.
Rim Diameter - The following number, in this case, 22.5, is the diameter. This does not apply to the diameter of the whole tire, but rather the semi-truck wheel diameter (the hole in the center of the tire). You would need a 22.5-inch wheel to fit this tire.
When reading the sidewall, you will encounter two additional numbers.
Load index - This number will indicate how much weight or load carrying capacity a single tire can hold. For example, 89 = 1,279 pounds, while 88 = 1,235 pounds.
Speed rating - You will see a speed rating letter at the end of the string. This indicates how fast the tire can go under its maximum load. A tire can go faster than this number at a lower load, but typically the tires can withstand a higher speed than the speed limits you will encounter.
No matter the size of your fleet or the needs that your trucks meet, we have the right tires for you.
Whether you are looking for steer tires, drive tires, trailer tires or all position tires, we can outfit every wheel position of your commercial truck. Whether you’re looking for a top-tier fuel-efficient tire or a more economical option, we carry a wide variety of brands and semi-truck tire sizes, and we can get you and your truck back on the road quickly.
FIND A GCR DEALER NEAR YOU
by Tim Plaehn
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.
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.
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.
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.
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.
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.
Tire sizes.
Tire sizes are represented by outer diameter, section width and static radius for each truck and passenger car tire designation.
1. Tire sizes in accordance with GOST R 52899-2007 “Pneumatic tires for cargo motor vehicles and trailers.
Specifications".
Table 1. Light truck tires.
| Tire designation | Basic dimensions, mm | Static radius ±1.0% (reference) | |
| OD ±1.0% | Profile width, max | ||
| 185/80R15C | 674 | 188 | 310 |
| 215/80R16C | 755 | 218 | 355 |
| 225/75R16C | 744 | 228 | 338 |
| 5.90-13C | 620 | 154 | 292 |
| 6.40-13C | 645 | 172 | 303 |
| 215/90-15С | 777 | 218 | 364 |
| 6.50-16C | 760 | 180 | 360 |
| 175/80-16С | 692 | 178 | 326 |
Designation of light truck tire 185/80R15C:
185 - designation of the nominal width of the tire profile in millimeters;
80 — nominal ratio of tire profile height to its width, %;
15 - designation of the nominal fitting diameter of the rim in inches;
C is a symbol identifying a light truck tyre.
R - radial tire.
Table 2. Tires for trucks.
| Tire designation | Rim designation | Basic dimensions, mm | Static radius ±1.5% (reference) | ||
| recommended blown | tolerable | OD ±1.5% | Profile width, max | ||
| Diagonal | |||||
| 7.50-20 | 6.0-20 | 6.5-20 | 928 | 213 | 443 |
| 8.25-20 | 6.5-20 | 6.0-20 | 970 | 234 | 462 |
| 9.00-20 | 7.0-20 | 6.5-20 | 1012 | 256 | 481 |
| 10.00-20 | 7.5-20 | 8.0-20 | 1050 | 275 | 498 |
| 11.00-20 | 8.0-20 | 8.5-20 | 1080 | 291 | 511 | nine0027
12. 00-20 | 8.5-20 | 9.0-20 | 1120 | 312 | 529 |
| 12.00-24 | 8.5-24 | 9.0-24 | 1220 | 312 | 576 |
| Radial chamber | |||||
| 7.50R20 | 6.0-20 | 6.5-20 | 928 | 210 | 440 |
| 8.25R20 | 6.5-20 | nine0021 6.0-20962 | 230 | 453 | |
| 9.00R20 | 7.0-20 | 6.5-20 | 1018 | 258 | 475 |
| 10.00R20 | 7.5-20 | 7.0-20 8.0-20 | 1052 | 275 | 491 |
| 11.00R20 | 8.0-20 | 8.5-20 | 1082 | 286 | 505 |
| 12.00R20 | 8.5-20 | 9.0-20 | 1122 | 313 | 526 |
| 12/80R20 | 8. 5-20 | 9.0-20 | 1008 | 305 | 472 |
| 12.00R24 | 8.5-24 | 9.0-24 | 1226 | 313 | 570 |
| 8.25R15 | 6.6-15 | 7.0-15 | 836 | 234 | 385 |
| Radial Tubeless | |||||
| 10R22.5 | 7.50×22.5 | 6.75×22.5 | 1020 | 254 | 476 |
| 11R22.5 | 8.25×22.5 | 7.50×22.5 | 1050 | 279 | 489 |
| 12R22.5 | 9.00×22.5 | 8.25×22.5 | 1084 | 300 | 504 |
| 385/65R22.5 | 11.75×22.5 | 12.25×22.5 | 1072 | 389 | 505 |
| 275/80R22.5 | 8.25×22.5 | 7.50×22.5 | 1012 | 276 | 470 |
295/80R22. 5 | 9.00×22.5 | 8.25×22.5 | 1044 | 298 | 490 |
| 315/80R22.5 | 9.00×22.5 | 9.75×22.5 | 1076 | 312 | 499 |
| 350/80R22.5 | 11.75×22.5 | 12.25×22.5 | 1122 | 355 | 526 |
| 11/70R22.5 | 8.25×22.5 | 7.50×22.5 | 962 | 279 | 447 |
| 315/70R22.5 | 9.00×22.5 | 8.25×22.5 | 1014 | 312 | 467 |
| 425/65R22.5 | 13.00×22.5 | 14.00×22.5 | 1122 | 425 | 525 |
Tire designation example: 8.25R20 is the designation of the tire, where 8.25 is the designation of the nominal section width of the tire in inches, R is the letter index of the radial tire, 20 is the designation of the nominal rim diameter in inches.
Note.
Tire profile width measured on the recommended rim. When mounted on a permitted rim, the profile width changes by 40% of the difference between the widths of the recommended and permitted rims. nine0007
2. Tire sizes for passenger cars according to GOST 4754-97 are shown in Table 3.
Table 3.
45-13 An example of tire designation 165/80 R13: 165 - designation of the nominal width of the tire profile in millimeters, 80 - series (nominal ratio of the height of the profile to its width in percent), R - letter index of the radial tire, 13 - designation of the tire diameter , corresponding to the nominal diameter of the rim in inches; nine0007
3. Tire sizes according to GOST 13298-90 “Tyres with adjustable pressure. Specifications".
Table 4.
| Ply rate | Rim designation | Tire dimensions, mm | |||
| 12.00-18 | 8 | 465-228 (228G-457) | 1084±8 | 337 | 505±5 |
| 13.00-18 | nine0021 8 465-228 (228G-457) | 1132±8 | 351 | 525±5 | |
12. 00-20 | 8 | 514-228 (228G-508) | 1142±8 | 335 | 530±5 |
| 14.00-20 | 10 | 515-254 (254G-508) | 1260±10 | 390 | 583±5 |
| 16.00-20 | 10 | 515-292 (292-508) | 1384±10 | 460 | 632±5 |
| 1200 x 500-508 | 10 | 514-400 (400G-508) | 1177±15 | 481 | 540±7 |
| 1220 x 400-533 | 10 | 533-310 (310-533) | 1200±15 | 418 | 560±7 |
| 1300 x 530-533 | 12 | 533-440 (440-533) | 1280±15 | nine0021 525585±7 | |
| 1500 x 600-635 | 10 14 | 500-635 | 1500±15 | 610 | 680±10 |
| 1600 x 600-685 | 24 | 500-685 | 1590±15 | 600 | 725±10 |
Example 1.
Wide profile tire 1300 x 530 - 533, where
1300 is the conditional outer diameter of the tires in millimeters; nine0007
530 - conditional width of the tire section in mm;
533 – conditional rim diameter in mm.
Example 2. Tire of the usual profile 12.00-18, where 12.00 is a conditional width of the profile in inches; 18 - conditional fit diameter of the rim in inches. nine0003
90,000 Table of cargo tires for disk size (Using Tire Disk)Search for goods
Non-chamber tires (TL)
| 9000 | 17.5 × 6.75 | |
|---|---|---|
| 8R17.5 | 8R17.5 | |
| 8.5R17.5 | 8.5R17.5 | |
| 9.5R17.5 | 9.5R17.5 | |
| 205/65R17.5 | 10R17.5 | |
| 205/75R17.5 | 205/65R17.5/65r17.5/65r17. 5/65r17.5/65rd 75r17.5 | 205/75r17.5 |
| 225/75R17.5 | 215/75R17.5 | 235/75R17.5 | 225/75R17.575R17.5 |
| 245/70R17.5 | ||
| 245/75R17.5 | ||
| 265/70R17.5 |
| ДИАМЕТР 19.5 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 19.5×6.75 | 19.5×7.50 | 19.5 × 8.25 | 19.5 × 11.75 | 19.5 × 13.00 | 19.5.5 | 385/55R19.5 | 425/55R19.5 | 425/55R19.5 | |
| 265/70r19.5 | 285/70r5/70r 65R19.5 | 435/50R19.5 | 435/50R19.5 | ||||||
| 265/70R19.5 | 285/70R19.5 | 305/70R19. 5 | 900/444/445/445/444/40021 | . 5 |
| DIAMETER 22.5 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 22.5×6.75 | 22.5×7.50 | 22.5×8.25 | 22.5×9.00 | 22.5×11.75 | 22.5×13.00 | 22.5×14.00 | ||||
| 8R22.5 | 10R22.5 | 11R22.5 | 12r22.5 | 365/70r22.5 | 415/45r22.5 | 415/45r22.5 . 11R22.512R22.5 | 13r22.5 | 375/90r22.5 | 425/65r22.5 | 425/65r22.5 |
| 10r22.5 | 255/70r22 /60r22.5385/55r22.5 | 445/75r22.5 | 435/45r22.5 | 255/70r22.5 | 265/60r22.5 | 265/65/65/65/65/65/65/65/65/65/65/ 295/60R22. 5 | 385/65R22.5 | 445/65R22.5 | ||
| 275/70R22.5 | 275/70r22.5 | 295/80r22.5 | 445/75r22.5 | |||||||
| 275/80r22.5 | 275/80r21 275/80r21 275/80r 275/80r | |||||||||
| 285/60R22.5 | 305/70R22.5 | |||||||||
| 295/80R22.5 | 315/60R22 .5 | |||||||||
| 305/70R22.5 | 315/70R22.5 | |||||||||
| 315/75R22.5 | ||||||||||
| 315/80r22.5 |
Cammary tires (TT)
,00070018
