Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 275/55-20 | 305/45-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 31.91 (810.5) | 30.81 (782.5) | -1.1 (-28) -3.5% |
| Width inches (mm) | 10.83 (275) | 12.01 (305) | 1.18 (30) 10.9% |
| Circum. inches (mm) | 100.25 (2546.26) | 96.78 (2458.3) | -3.46 (-87.96) -3.5% |
| Sidewall Height inches (mm) | 5.95 (151.25) | 5.4 (137.25) | -0.55 (-14) -9.3% |
| Revolutions per mile (km) | 632.04 (392.73) | 654.66 (406.79) | 22.62 (14.05) 3.6% |
305/45-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.31 mph (31.07 km/h) |
| 25 mph (40.23 km/h) | 24.14 mph (38.84 km/h) |
| 30 mph (48.28 km/h) | 28.96 mph (46.61 km/h) |
| 35 mph (56.33 km/h) | 33.79 mph (54.38 km/h) |
| 40 mph (64.37 km/h) | 38.62 mph (62.15 km/h) |
| 45 mph (72.42 km/h) | 43.45 mph (69.92 km/h) |
| 50 mph (80.47 km/h) | 48.27 mph (77.69 km/h) |
| 55 mph (88.51 km/h) | 53.1 mph (85.46 km/h) |
| 60 mph (96.56 km/h) | 57.93 mph (93.22 km/h) |
| 65 mph (104.61 km/h) | 62.75 mph (100.99 km/h) |
| 70 mph (112.65 km/h) | 67.58 mph (108.76 km/h) |
| 75 mph (120.7 km/h) | 72.41 mph (116.53 km/h) |
| 80 mph (128.75 km/h) | 77.24 mph (124.3 km/h) |
| 85 mph (136.79 km/h) | 82.06 mph (132.07 km/h) |
| 90 mph (144.84 km/h) | 86.89 mph (139.84 km/h) |
| 95 mph (152.89 km/h) | 91.72 mph (147.61 km/h) |
| 100 mph (160.93 km/h) | 96.55 mph (155.37 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1666 | 1935 | 2084 | 2176 | 2276 | 2347 | 2425 | 2517 | 2644 | 2772 | 2914 | 3027 | 3233 | 3460 | 3637 | 3750 | 3814 | 4048 | 4374 | 5083 |
Better Fuel Economy Factory Ratios Increased Power
