Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 275/40-21 | 275/45-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 29.66 (753.4) | 30.74 (780.9) | 1.08 (27.5) 3.7% |
| Width inches (mm) | 10.83 (275) | 10.83 (275) | 0 (0) 0% |
| Circum. inches (mm) | 93.18 (2366.88) | 96.59 (2453.27) | 3.4 (86.39) 3.7% |
| Sidewall Height inches (mm) | 4.33 (110) | 4.87 (123.75) | 0.54 (13.75) 12.5% |
| Revolutions per mile (km) | 679.94 (422.5) | 656 (407.62) | -23.94 (-14.88) -3.5% |
275/45-21 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.73 mph (33.36 km/h) |
| 25 mph (40.23 km/h) | 25.91 mph (41.7 km/h) |
| 30 mph (48.28 km/h) | 31.1 mph (50.04 km/h) |
| 35 mph (56.33 km/h) | 36.28 mph (58.38 km/h) |
| 40 mph (64.37 km/h) | 41.46 mph (66.72 km/h) |
| 45 mph (72.42 km/h) | 46.64 mph (75.06 km/h) |
| 50 mph (80.47 km/h) | 51.83 mph (83.4 km/h) |
| 55 mph (88.51 km/h) | 57.01 mph (91.74 km/h) |
| 60 mph (96.56 km/h) | 62.19 mph (100.09 km/h) |
| 65 mph (104.61 km/h) | 67.37 mph (108.43 km/h) |
| 70 mph (112.65 km/h) | 72.56 mph (116.77 km/h) |
| 75 mph (120.7 km/h) | 77.74 mph (125.11 km/h) |
| 80 mph (128.75 km/h) | 82.92 mph (133.45 km/h) |
| 85 mph (136.79 km/h) | 88.1 mph (141.79 km/h) |
| 90 mph (144.84 km/h) | 93.29 mph (150.13 km/h) |
| 95 mph (152.89 km/h) | 98.47 mph (158.47 km/h) |
| 100 mph (160.93 km/h) | 103.65 mph (166.81 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1669 | 1939 | 2089 | 2181 | 2280 | 2351 | 2430 | 2522 | 2650 | 2778 | 2920 | 3033 | 3239 | 3467 | 3644 | 3758 | 3822 | 4056 | 4383 | 5093 |
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