Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 275/45-21 | 255/65-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 30.74 (780.9) | 31.05 (788.7) | 0.31 (7.8) 1% |
| Width inches (mm) | 10.83 (275) | 10.04 (255) | -0.79 (-20) -7.3% |
| Circum. inches (mm) | 96.59 (2453.27) | 97.55 (2477.77) | 0.96 (24.5) 1% |
| Sidewall Height inches (mm) | 4.87 (123.75) | 6.53 (165.75) | 1.65 (42) 33.9% |
| Revolutions per mile (km) | 656 (407.62) | 649.51 (403.59) | -6.49 (-4.03) -1% |
255/65-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.2 mph (32.51 km/h) |
| 25 mph (40.23 km/h) | 25.25 mph (40.64 km/h) |
| 30 mph (48.28 km/h) | 30.3 mph (48.76 km/h) |
| 35 mph (56.33 km/h) | 35.35 mph (56.89 km/h) |
| 40 mph (64.37 km/h) | 40.4 mph (65.02 km/h) |
| 45 mph (72.42 km/h) | 45.45 mph (73.14 km/h) |
| 50 mph (80.47 km/h) | 50.5 mph (81.27 km/h) |
| 55 mph (88.51 km/h) | 55.55 mph (89.4 km/h) |
| 60 mph (96.56 km/h) | 60.6 mph (97.53 km/h) |
| 65 mph (104.61 km/h) | 65.65 mph (105.65 km/h) |
| 70 mph (112.65 km/h) | 70.7 mph (113.78 km/h) |
| 75 mph (120.7 km/h) | 75.75 mph (121.91 km/h) |
| 80 mph (128.75 km/h) | 80.8 mph (130.03 km/h) |
| 85 mph (136.79 km/h) | 85.85 mph (138.16 km/h) |
| 90 mph (144.84 km/h) | 90.9 mph (146.29 km/h) |
| 95 mph (152.89 km/h) | 95.95 mph (154.42 km/h) |
| 100 mph (160.93 km/h) | 101 mph (162.54 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 | 1920 | 2068 | 2159 | 2258 | 2328 | 2405 | 2497 | 2624 | 2750 | 2891 | 3003 | 3207 | 3432 | 3608 | 3721 | 3784 | 4016 | 4340 | 5043 |
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