Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 275/45-21 | 315/40-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 30.74 (780.9) | 30.92 (785.4) | 0.18 (4.5) 0.6% |
| Width inches (mm) | 10.83 (275) | 12.4 (315) | 1.57 (40) 14.5% |
| Circum. inches (mm) | 96.59 (2453.27) | 97.14 (2467.41) | 0.56 (14.14) 0.6% |
| Sidewall Height inches (mm) | 4.87 (123.75) | 4.96 (126) | 0.09 (2.25) 1.8% |
| Revolutions per mile (km) | 656 (407.62) | 652.24 (405.28) | -3.76 (-2.34) -0.6% |
315/40-21 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.12 mph (32.37 km/h) |
| 25 mph (40.23 km/h) | 25.14 mph (40.47 km/h) |
| 30 mph (48.28 km/h) | 30.17 mph (48.56 km/h) |
| 35 mph (56.33 km/h) | 35.2 mph (56.65 km/h) |
| 40 mph (64.37 km/h) | 40.23 mph (64.74 km/h) |
| 45 mph (72.42 km/h) | 45.26 mph (72.84 km/h) |
| 50 mph (80.47 km/h) | 50.29 mph (80.93 km/h) |
| 55 mph (88.51 km/h) | 55.32 mph (89.02 km/h) |
| 60 mph (96.56 km/h) | 60.35 mph (97.12 km/h) |
| 65 mph (104.61 km/h) | 65.37 mph (105.21 km/h) |
| 70 mph (112.65 km/h) | 70.4 mph (113.3 km/h) |
| 75 mph (120.7 km/h) | 75.43 mph (121.4 km/h) |
| 80 mph (128.75 km/h) | 80.46 mph (129.49 km/h) |
| 85 mph (136.79 km/h) | 85.49 mph (137.58 km/h) |
| 90 mph (144.84 km/h) | 90.52 mph (145.68 km/h) |
| 95 mph (152.89 km/h) | 95.55 mph (153.77 km/h) |
| 100 mph (160.93 km/h) | 100.58 mph (161.86 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1660 | 1928 | 2077 | 2168 | 2267 | 2338 | 2416 | 2507 | 2635 | 2762 | 2903 | 3016 | 3221 | 3447 | 3623 | 3736 | 3800 | 4033 | 4358 | 5064 |
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