Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/45-18 | 275/40-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.81 (731.7) | 28.66 (728) | -0.15 (-3.7) -0.5% |
| Width inches (mm) | 12.01 (305) | 10.83 (275) | -1.18 (-30) -9.8% |
| Circum. inches (mm) | 90.5 (2298.7) | 90.04 (2287.08) | -0.46 (-11.62) -0.5% |
| Sidewall Height inches (mm) | 5.4 (137.25) | 4.33 (110) | -1.07 (-27.25) -19.9% |
| Revolutions per mile (km) | 700.11 (435.03) | 703.67 (437.24) | 3.56 (2.21) 0.5% |
275/40-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.9 mph (32.02 km/h) |
| 25 mph (40.23 km/h) | 24.87 mph (40.03 km/h) |
| 30 mph (48.28 km/h) | 29.85 mph (48.04 km/h) |
| 35 mph (56.33 km/h) | 34.82 mph (56.04 km/h) |
| 40 mph (64.37 km/h) | 39.8 mph (64.05 km/h) |
| 45 mph (72.42 km/h) | 44.77 mph (72.05 km/h) |
| 50 mph (80.47 km/h) | 49.75 mph (80.06 km/h) |
| 55 mph (88.51 km/h) | 54.72 mph (88.07 km/h) |
| 60 mph (96.56 km/h) | 59.7 mph (96.07 km/h) |
| 65 mph (104.61 km/h) | 64.67 mph (104.08 km/h) |
| 70 mph (112.65 km/h) | 69.65 mph (112.08 km/h) |
| 75 mph (120.7 km/h) | 74.62 mph (120.09 km/h) |
| 80 mph (128.75 km/h) | 79.6 mph (128.1 km/h) |
| 85 mph (136.79 km/h) | 84.57 mph (136.1 km/h) |
| 90 mph (144.84 km/h) | 89.54 mph (144.11 km/h) |
| 95 mph (152.89 km/h) | 94.52 mph (152.11 km/h) |
| 100 mph (160.93 km/h) | 99.49 mph (160.12 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1791 | 2080 | 2240 | 2339 | 2446 | 2522 | 2606 | 2705 | 2842 | 2979 | 3132 | 3254 | 3475 | 3719 | 3909 | 4031 | 4100 | 4351 | 4702 | 5464 |
Better Fuel Economy Factory Ratios Increased Power
