Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 315/35-21 | 315/40-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 29.68 (753.9) | 30.92 (785.4) | 1.24 (31.5) 4.2% |
| Width inches (mm) | 12.4 (315) | 12.4 (315) | 0 (0) 0% |
| Circum. inches (mm) | 93.25 (2368.45) | 97.14 (2467.41) | 3.9 (98.96) 4.2% |
| Sidewall Height inches (mm) | 4.34 (110.25) | 4.96 (126) | 0.62 (15.75) 14.3% |
| Revolutions per mile (km) | 679.49 (422.22) | 652.24 (405.28) | -27.25 (-16.93) -4% |
315/40-21 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.84 mph (33.53 km/h) |
| 25 mph (40.23 km/h) | 26.04 mph (41.91 km/h) |
| 30 mph (48.28 km/h) | 31.25 mph (50.3 km/h) |
| 35 mph (56.33 km/h) | 36.46 mph (58.68 km/h) |
| 40 mph (64.37 km/h) | 41.67 mph (67.06 km/h) |
| 45 mph (72.42 km/h) | 46.88 mph (75.45 km/h) |
| 50 mph (80.47 km/h) | 52.09 mph (83.83 km/h) |
| 55 mph (88.51 km/h) | 57.3 mph (92.21 km/h) |
| 60 mph (96.56 km/h) | 62.51 mph (100.6 km/h) |
| 65 mph (104.61 km/h) | 67.72 mph (108.98 km/h) |
| 70 mph (112.65 km/h) | 72.92 mph (117.36 km/h) |
| 75 mph (120.7 km/h) | 78.13 mph (125.74 km/h) |
| 80 mph (128.75 km/h) | 83.34 mph (134.13 km/h) |
| 85 mph (136.79 km/h) | 88.55 mph (142.51 km/h) |
| 90 mph (144.84 km/h) | 93.76 mph (150.89 km/h) |
| 95 mph (152.89 km/h) | 98.97 mph (159.28 km/h) |
| 100 mph (160.93 km/h) | 104.18 mph (167.66 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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