Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 315/40-19 | 315/40-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.92 (734.6) | 30.92 (785.4) | 2 (50.8) 6.9% |
| Width inches (mm) | 12.4 (315) | 12.4 (315) | 0 (0) 0% |
| Circum. inches (mm) | 90.86 (2307.81) | 97.14 (2467.41) | 6.28 (159.59) 6.9% |
| Sidewall Height inches (mm) | 4.96 (126) | 4.96 (126) | 0 (0) 0% |
| Revolutions per mile (km) | 697.35 (433.31) | 652.24 (405.28) | -45.1 (-28.03) -6.5% |
315/40-21 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.38 mph (34.41 km/h) |
| 25 mph (40.23 km/h) | 26.73 mph (43.02 km/h) |
| 30 mph (48.28 km/h) | 32.07 mph (51.62 km/h) |
| 35 mph (56.33 km/h) | 37.42 mph (60.22 km/h) |
| 40 mph (64.37 km/h) | 42.77 mph (68.83 km/h) |
| 45 mph (72.42 km/h) | 48.11 mph (77.43 km/h) |
| 50 mph (80.47 km/h) | 53.46 mph (86.03 km/h) |
| 55 mph (88.51 km/h) | 58.8 mph (94.64 km/h) |
| 60 mph (96.56 km/h) | 64.15 mph (103.24 km/h) |
| 65 mph (104.61 km/h) | 69.49 mph (111.84 km/h) |
| 70 mph (112.65 km/h) | 74.84 mph (120.44 km/h) |
| 75 mph (120.7 km/h) | 80.19 mph (129.05 km/h) |
| 80 mph (128.75 km/h) | 85.53 mph (137.65 km/h) |
| 85 mph (136.79 km/h) | 90.88 mph (146.25 km/h) |
| 90 mph (144.84 km/h) | 96.22 mph (154.86 km/h) |
| 95 mph (152.89 km/h) | 101.57 mph (163.46 km/h) |
| 100 mph (160.93 km/h) | 106.92 mph (172.06 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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