Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/45-17 | 315/30-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.52 (724.3) | 27.44 (697) | -1.07 (-27.3) -3.8% |
| Width inches (mm) | 12.8 (325) | 12.4 (315) | -0.39 (-10) -3.1% |
| Circum. inches (mm) | 89.58 (2275.46) | 86.21 (2189.69) | -3.38 (-85.77) -3.8% |
| Sidewall Height inches (mm) | 5.76 (146.25) | 3.72 (94.5) | -2.04 (-51.75) -35.4% |
| Revolutions per mile (km) | 707.26 (439.47) | 734.96 (456.68) | 27.7 (17.21) 3.9% |
315/30-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.25 mph (30.97 km/h) |
| 25 mph (40.23 km/h) | 24.06 mph (38.72 km/h) |
| 30 mph (48.28 km/h) | 28.87 mph (46.46 km/h) |
| 35 mph (56.33 km/h) | 33.68 mph (54.2 km/h) |
| 40 mph (64.37 km/h) | 38.49 mph (61.95 km/h) |
| 45 mph (72.42 km/h) | 43.3 mph (69.69 km/h) |
| 50 mph (80.47 km/h) | 48.12 mph (77.43 km/h) |
| 55 mph (88.51 km/h) | 52.93 mph (85.18 km/h) |
| 60 mph (96.56 km/h) | 57.74 mph (92.92 km/h) |
| 65 mph (104.61 km/h) | 62.55 mph (100.66 km/h) |
| 70 mph (112.65 km/h) | 67.36 mph (108.41 km/h) |
| 75 mph (120.7 km/h) | 72.17 mph (116.15 km/h) |
| 80 mph (128.75 km/h) | 76.98 mph (123.9 km/h) |
| 85 mph (136.79 km/h) | 81.8 mph (131.64 km/h) |
| 90 mph (144.84 km/h) | 86.61 mph (139.38 km/h) |
| 95 mph (152.89 km/h) | 91.42 mph (147.13 km/h) |
| 100 mph (160.93 km/h) | 96.23 mph (154.87 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 |
Better Fuel Economy Factory Ratios Increased Power
