Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 285/45-20 | 305/40-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 30.1 (764.5) | 29.61 (752) | -0.49 (-12.5) -1.6% |
| Width inches (mm) | 11.22 (285) | 12.01 (305) | 0.79 (20) 7% |
| Circum. inches (mm) | 94.56 (2401.75) | 93.01 (2362.48) | -1.55 (-39.27) -1.6% |
| Sidewall Height inches (mm) | 5.05 (128.25) | 4.8 (122) | -0.25 (-6.25) -4.9% |
| Revolutions per mile (km) | 670.07 (416.36) | 681.21 (423.28) | 11.14 (6.92) 1.7% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.67 mph (31.66 km/h) |
| 25 mph (40.23 km/h) | 24.59 mph (39.58 km/h) |
| 30 mph (48.28 km/h) | 29.51 mph (47.49 km/h) |
| 35 mph (56.33 km/h) | 34.43 mph (55.41 km/h) |
| 40 mph (64.37 km/h) | 39.35 mph (63.32 km/h) |
| 45 mph (72.42 km/h) | 44.26 mph (71.24 km/h) |
| 50 mph (80.47 km/h) | 49.18 mph (79.15 km/h) |
| 55 mph (88.51 km/h) | 54.1 mph (87.07 km/h) |
| 60 mph (96.56 km/h) | 59.02 mph (94.98 km/h) |
| 65 mph (104.61 km/h) | 63.94 mph (102.9 km/h) |
| 70 mph (112.65 km/h) | 68.86 mph (110.81 km/h) |
| 75 mph (120.7 km/h) | 73.77 mph (118.73 km/h) |
| 80 mph (128.75 km/h) | 78.69 mph (126.64 km/h) |
| 85 mph (136.79 km/h) | 83.61 mph (134.56 km/h) |
| 90 mph (144.84 km/h) | 88.53 mph (142.47 km/h) |
| 95 mph (152.89 km/h) | 93.45 mph (150.39 km/h) |
| 100 mph (160.93 km/h) | 98.36 mph (158.3 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1734 | 2014 | 2169 | 2265 | 2368 | 2442 | 2523 | 2619 | 2752 | 2884 | 3032 | 3150 | 3364 | 3600 | 3784 | 3902 | 3969 | 4212 | 4551 | 5289 |
Better Fuel Economy Factory Ratios Increased Power
