31.9" tall, 12.4" wide, 5.0" sidewall
A 315/40R22 tire is 31.9 inches (811 mm) tall and 12.4 inches wide. The sidewall is 40% of the width, 5.0 inches, on a 22-inch wheel, and the tire turns about 632 times per mile.
In flotation terms that is about 31.9x12.4R22. People often call it a 32-inch tire.
The size most often compared with it is 305/40R22, which is 0.3" shorter (−1.0%). At an indicated 60 mph you would be doing 59.4 mph on it.
| Current | New | Difference |
|---|
| Shows | Actual speed |
|---|
Same 22" wheel, within 20 mm of width and 10 points of aspect ratio.
| Size | Diameter | Width | Sidewall | vs 315/40R22 | |
|---|---|---|---|---|---|
| 305/40R22 | 31.6" | 12.0" | 4.8" | −1.0% | |
| 325/40R22 | 32.2" | 12.8" | 5.1" | +1.0% | |
| 295/45R22 | 32.5" | 11.6" | 5.2" | +1.7% | |
| 295/40R22 | 31.3" | 11.6" | 4.6" | −2.0% | |
| 305/45R22 | 32.8" | 12.0" | 5.4" | +2.8% | |
| 325/35R22 | 31.0" | 12.8" | 4.5" | −3.0% | |
| 33x12.50R22 | 33.0" | 12.5" | 5.5" | +3.4% | |
| 315/45R22 | 33.2" | 12.4" | 5.6" | +3.9% | |
| 305/35R22 | 30.4" | 12.0" | 4.2" | −4.7% | |
| 325/45R22 | 33.5" | 12.8" | 5.8" | +5.0% |
Sizes within 2% of 31.9" on 20" or 24" wheels.
| Size | Diameter | Width | Sidewall | vs 315/40R22 | |
|---|---|---|---|---|---|
| 275/55R20 | 31.9" | 10.8" | 6.0" | −0.0% | |
| 285/35R24 | 31.9" | 11.2" | 3.9" | −0.2% | |
| 305/50R20 | 32.0" | 12.0" | 6.0" | +0.3% | |
| 255/60R20 | 32.0" | 10.0" | 6.0" | +0.4% | |
| 295/50R20 | 31.6" | 11.6" | 5.8" | −1.0% | |
| 275/35R24 | 31.6" | 10.8" | 3.8" | −1.1% |
Actual speed when the speedometer is calibrated for 315/40R22.
| Speedometer shows | on 305/40R22 | on 325/40R22 | on 295/45R22 |
|---|---|---|---|
| 30 mph | 29.7 mph | 30.3 mph | 30.5 mph |
| 45 mph | 44.6 mph | 45.4 mph | 45.7 mph |
| 60 mph | 59.4 mph | 60.6 mph | 61.0 mph |
| 70 mph | 69.3 mph | 70.7 mph | 71.2 mph |
31.9 inches (811 mm). The sidewall is 5.0 inches.
12.4 inches (315 mm) section width, measured sidewall to sidewall.
About 31.9x12.4R22.
305/40R22 is −1.0% in diameter, within the common 3% guideline. It is 0.4" narrower.