Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 315/25-20 | 305/30-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 26.2 (665.5) | 27.2 (691) | 1 (25.5) 3.8% |
| Width inches (mm) | 12.4 (315) | 12.01 (305) | -0.39 (-10) -3.2% |
| Circum. inches (mm) | 82.31 (2090.73) | 85.47 (2170.84) | 3.15 (80.11) 3.8% |
| Sidewall Height inches (mm) | 3.1 (78.75) | 3.6 (91.5) | 0.5 (12.75) 16.2% |
| Revolutions per mile (km) | 769.75 (478.3) | 741.35 (460.65) | -28.41 (-17.65) -3.7% |
305/30-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.77 mph (33.42 km/h) |
| 25 mph (40.23 km/h) | 25.96 mph (41.78 km/h) |
| 30 mph (48.28 km/h) | 31.15 mph (50.13 km/h) |
| 35 mph (56.33 km/h) | 36.34 mph (58.49 km/h) |
| 40 mph (64.37 km/h) | 41.53 mph (66.84 km/h) |
| 45 mph (72.42 km/h) | 46.72 mph (75.2 km/h) |
| 50 mph (80.47 km/h) | 51.92 mph (83.55 km/h) |
| 55 mph (88.51 km/h) | 57.11 mph (91.91 km/h) |
| 60 mph (96.56 km/h) | 62.3 mph (100.26 km/h) |
| 65 mph (104.61 km/h) | 67.49 mph (108.62 km/h) |
| 70 mph (112.65 km/h) | 72.68 mph (116.97 km/h) |
| 75 mph (120.7 km/h) | 77.87 mph (125.33 km/h) |
| 80 mph (128.75 km/h) | 83.07 mph (133.68 km/h) |
| 85 mph (136.79 km/h) | 88.26 mph (142.04 km/h) |
| 90 mph (144.84 km/h) | 93.45 mph (150.39 km/h) |
| 95 mph (152.89 km/h) | 98.64 mph (158.75 km/h) |
| 100 mph (160.93 km/h) | 103.83 mph (167.1 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1887 | 2192 | 2360 | 2465 | 2577 | 2657 | 2746 | 2850 | 2994 | 3139 | 3300 | 3428 | 3661 | 3918 | 4118 | 4247 | 4319 | 4584 | 4953 | 5756 |
Better Fuel Economy Factory Ratios Increased Power
