Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/25-21 | 315/30-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 27.4 (695.9) | 27.44 (697) | 0.04 (1.1) 0.2% |
| Width inches (mm) | 12.8 (325) | 12.4 (315) | -0.39 (-10) -3.1% |
| Circum. inches (mm) | 86.07 (2186.23) | 86.21 (2189.69) | 0.14 (3.46) 0.2% |
| Sidewall Height inches (mm) | 3.2 (81.25) | 3.72 (94.5) | 0.52 (13.25) 16.3% |
| Revolutions per mile (km) | 736.13 (457.41) | 734.96 (456.68) | -1.16 (-0.72) -0.2% |
315/30-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.03 mph (32.24 km/h) |
| 25 mph (40.23 km/h) | 25.04 mph (40.3 km/h) |
| 30 mph (48.28 km/h) | 30.05 mph (48.36 km/h) |
| 35 mph (56.33 km/h) | 35.06 mph (56.42 km/h) |
| 40 mph (64.37 km/h) | 40.06 mph (64.48 km/h) |
| 45 mph (72.42 km/h) | 45.07 mph (72.54 km/h) |
| 50 mph (80.47 km/h) | 50.08 mph (80.59 km/h) |
| 55 mph (88.51 km/h) | 55.09 mph (88.65 km/h) |
| 60 mph (96.56 km/h) | 60.09 mph (96.71 km/h) |
| 65 mph (104.61 km/h) | 65.1 mph (104.77 km/h) |
| 70 mph (112.65 km/h) | 70.11 mph (112.83 km/h) |
| 75 mph (120.7 km/h) | 75.12 mph (120.89 km/h) |
| 80 mph (128.75 km/h) | 80.13 mph (128.95 km/h) |
| 85 mph (136.79 km/h) | 85.13 mph (137.01 km/h) |
| 90 mph (144.84 km/h) | 90.14 mph (145.07 km/h) |
| 95 mph (152.89 km/h) | 95.15 mph (153.13 km/h) |
| 100 mph (160.93 km/h) | 100.16 mph (161.19 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1870 | 2173 | 2340 | 2443 | 2555 | 2634 | 2722 | 2825 | 2969 | 3112 | 3271 | 3398 | 3629 | 3884 | 4083 | 4210 | 4282 | 4545 | 4911 | 5707 |
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