Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/70-17 | 305/55-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 33.81 (858.8) | 33.21 (843.5) | -0.6 (-15.3) -1.8% |
| Width inches (mm) | 12.01 (305) | 12.01 (305) | 0 (0) 0% |
| Circum. inches (mm) | 106.22 (2698) | 104.33 (2649.93) | -1.89 (-48.07) -1.8% |
| Sidewall Height inches (mm) | 8.41 (213.5) | 6.6 (167.75) | -1.8 (-45.75) -21.4% |
| Revolutions per mile (km) | 596.5 (370.64) | 607.31 (377.37) | 10.82 (6.72) 1.8% |
305/55-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.64 mph (31.61 km/h) |
| 25 mph (40.23 km/h) | 24.55 mph (39.52 km/h) |
| 30 mph (48.28 km/h) | 29.47 mph (47.42 km/h) |
| 35 mph (56.33 km/h) | 34.38 mph (55.32 km/h) |
| 40 mph (64.37 km/h) | 39.29 mph (63.23 km/h) |
| 45 mph (72.42 km/h) | 44.2 mph (71.13 km/h) |
| 50 mph (80.47 km/h) | 49.11 mph (79.03 km/h) |
| 55 mph (88.51 km/h) | 54.02 mph (86.94 km/h) |
| 60 mph (96.56 km/h) | 58.93 mph (94.84 km/h) |
| 65 mph (104.61 km/h) | 63.84 mph (102.74 km/h) |
| 70 mph (112.65 km/h) | 68.75 mph (110.65 km/h) |
| 75 mph (120.7 km/h) | 73.66 mph (118.55 km/h) |
| 80 mph (128.75 km/h) | 78.57 mph (126.45 km/h) |
| 85 mph (136.79 km/h) | 83.49 mph (134.36 km/h) |
| 90 mph (144.84 km/h) | 88.4 mph (142.26 km/h) |
| 95 mph (152.89 km/h) | 93.31 mph (150.16 km/h) |
| 100 mph (160.93 km/h) | 98.22 mph (158.07 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1546 | 1795 | 1934 | 2019 | 2111 | 2177 | 2249 | 2335 | 2453 | 2571 | 2703 | 2808 | 2999 | 3209 | 3374 | 3479 | 3538 | 3755 | 4058 | 4715 |
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