Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/40-22 | 315/40-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 32.24 (818.8) | 30.92 (785.4) | -1.31 (-33.4) -4.1% |
| Width inches (mm) | 12.8 (325) | 12.4 (315) | -0.39 (-10) -3.1% |
| Circum. inches (mm) | 101.27 (2572.34) | 97.14 (2467.41) | -4.13 (-104.93) -4.1% |
| Sidewall Height inches (mm) | 5.12 (130) | 4.96 (126) | -0.16 (-4) -3.1% |
| Revolutions per mile (km) | 625.64 (388.75) | 652.24 (405.28) | 26.61 (16.53) 4.3% |
315/40-21 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.18 mph (30.87 km/h) |
| 25 mph (40.23 km/h) | 23.98 mph (38.59 km/h) |
| 30 mph (48.28 km/h) | 28.78 mph (46.31 km/h) |
| 35 mph (56.33 km/h) | 33.57 mph (54.03 km/h) |
| 40 mph (64.37 km/h) | 38.37 mph (61.75 km/h) |
| 45 mph (72.42 km/h) | 43.16 mph (69.47 km/h) |
| 50 mph (80.47 km/h) | 47.96 mph (77.18 km/h) |
| 55 mph (88.51 km/h) | 52.76 mph (84.9 km/h) |
| 60 mph (96.56 km/h) | 57.55 mph (92.62 km/h) |
| 65 mph (104.61 km/h) | 62.35 mph (100.34 km/h) |
| 70 mph (112.65 km/h) | 67.14 mph (108.06 km/h) |
| 75 mph (120.7 km/h) | 71.94 mph (115.78 km/h) |
| 80 mph (128.75 km/h) | 76.74 mph (123.5 km/h) |
| 85 mph (136.79 km/h) | 81.53 mph (131.21 km/h) |
| 90 mph (144.84 km/h) | 86.33 mph (138.93 km/h) |
| 95 mph (152.89 km/h) | 91.12 mph (146.65 km/h) |
| 100 mph (160.93 km/h) | 95.92 mph (154.37 km/h) |
| 2.35 | 2.73 | 2.94 | 3.07 | 3.21 | 3.31 | 3.42 | 3.55 | 3.73 | 3.91 | 4.11 | 4.27 | 4.56 | 4.88 | 5.13 | 5.29 | 5.38 | 5.71 | 6.17 | 7.17 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1660 | 1928 | 2077 | 2168 | 2267 | 2338 | 2416 | 2507 | 2635 | 2762 | 2903 | 3016 | 3221 | 3447 | 3623 | 3736 | 3800 | 4033 | 4358 | 5064 |
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