Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/45-20 | 375/45-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 30.81 (782.5) | 33.29 (845.5) | 2.48 (63) 8.1% |
| Width inches (mm) | 12.01 (305) | 14.76 (375) | 2.76 (70) 23% |
| Circum. inches (mm) | 96.78 (2458.3) | 104.58 (2656.22) | 7.79 (197.92) 8.1% |
| Sidewall Height inches (mm) | 5.4 (137.25) | 6.64 (168.75) | 1.24 (31.5) 23% |
| Revolutions per mile (km) | 654.66 (406.79) | 605.88 (376.47) | -48.78 (-30.31) -7.5% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.61 mph (34.78 km/h) |
| 25 mph (40.23 km/h) | 27.01 mph (43.47 km/h) |
| 30 mph (48.28 km/h) | 32.42 mph (52.17 km/h) |
| 35 mph (56.33 km/h) | 37.82 mph (60.86 km/h) |
| 40 mph (64.37 km/h) | 43.22 mph (69.56 km/h) |
| 45 mph (72.42 km/h) | 48.62 mph (78.25 km/h) |
| 50 mph (80.47 km/h) | 54.03 mph (86.95 km/h) |
| 55 mph (88.51 km/h) | 59.43 mph (95.64 km/h) |
| 60 mph (96.56 km/h) | 64.83 mph (104.34 km/h) |
| 65 mph (104.61 km/h) | 70.23 mph (113.03 km/h) |
| 70 mph (112.65 km/h) | 75.64 mph (121.72 km/h) |
| 75 mph (120.7 km/h) | 81.04 mph (130.42 km/h) |
| 80 mph (128.75 km/h) | 86.44 mph (139.11 km/h) |
| 85 mph (136.79 km/h) | 91.84 mph (147.81 km/h) |
| 90 mph (144.84 km/h) | 97.25 mph (156.5 km/h) |
| 95 mph (152.89 km/h) | 102.65 mph (165.2 km/h) |
| 100 mph (160.93 km/h) | 108.05 mph (173.89 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1542 | 1791 | 1929 | 2014 | 2106 | 2172 | 2244 | 2329 | 2447 | 2565 | 2697 | 2802 | 2992 | 3202 | 3366 | 3471 | 3530 | 3746 | 4048 | 4704 |
Better Fuel Economy Factory Ratios Increased Power
