Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 275/45-21 | 255/55-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 30.74 (780.9) | 31.04 (788.5) | 0.3 (7.6) 1% |
| Width inches (mm) | 10.83 (275) | 10.04 (255) | -0.79 (-20) -7.3% |
| Circum. inches (mm) | 96.59 (2453.27) | 97.53 (2477.15) | 0.94 (23.88) 1% |
| Sidewall Height inches (mm) | 4.87 (123.75) | 5.52 (140.25) | 0.65 (16.5) 13.3% |
| Revolutions per mile (km) | 656 (407.62) | 649.68 (403.69) | -6.32 (-3.93) -1% |
255/55-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.19 mph (32.5 km/h) |
| 25 mph (40.23 km/h) | 25.24 mph (40.63 km/h) |
| 30 mph (48.28 km/h) | 30.29 mph (48.75 km/h) |
| 35 mph (56.33 km/h) | 35.34 mph (56.88 km/h) |
| 40 mph (64.37 km/h) | 40.39 mph (65 km/h) |
| 45 mph (72.42 km/h) | 45.44 mph (73.13 km/h) |
| 50 mph (80.47 km/h) | 50.49 mph (81.25 km/h) |
| 55 mph (88.51 km/h) | 55.54 mph (89.38 km/h) |
| 60 mph (96.56 km/h) | 60.58 mph (97.5 km/h) |
| 65 mph (104.61 km/h) | 65.63 mph (105.63 km/h) |
| 70 mph (112.65 km/h) | 70.68 mph (113.75 km/h) |
| 75 mph (120.7 km/h) | 75.73 mph (121.88 km/h) |
| 80 mph (128.75 km/h) | 80.78 mph (130 km/h) |
| 85 mph (136.79 km/h) | 85.83 mph (138.13 km/h) |
| 90 mph (144.84 km/h) | 90.88 mph (146.25 km/h) |
| 95 mph (152.89 km/h) | 95.92 mph (154.38 km/h) |
| 100 mph (160.93 km/h) | 100.97 mph (162.5 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1653 | 1921 | 2068 | 2160 | 2258 | 2329 | 2406 | 2498 | 2624 | 2751 | 2892 | 3004 | 3208 | 3433 | 3609 | 3722 | 3785 | 4017 | 4341 | 5044 |
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