Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 315/35-21 | 325/25-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 29.68 (753.9) | 27.4 (695.9) | -2.28 (-58) -7.7% |
| Width inches (mm) | 12.4 (315) | 12.8 (325) | 0.39 (10) 3.2% |
| Circum. inches (mm) | 93.25 (2368.45) | 86.07 (2186.23) | -7.17 (-182.21) -7.7% |
| Sidewall Height inches (mm) | 4.34 (110.25) | 3.2 (81.25) | -1.14 (-29) -26.3% |
| Revolutions per mile (km) | 679.49 (422.22) | 736.13 (457.41) | 56.63 (35.19) 8.3% |
325/25-21 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 18.46 mph (29.71 km/h) |
| 25 mph (40.23 km/h) | 23.08 mph (37.14 km/h) |
| 30 mph (48.28 km/h) | 27.69 mph (44.57 km/h) |
| 35 mph (56.33 km/h) | 32.31 mph (51.99 km/h) |
| 40 mph (64.37 km/h) | 36.92 mph (59.42 km/h) |
| 45 mph (72.42 km/h) | 41.54 mph (66.85 km/h) |
| 50 mph (80.47 km/h) | 46.15 mph (74.28 km/h) |
| 55 mph (88.51 km/h) | 50.77 mph (81.7 km/h) |
| 60 mph (96.56 km/h) | 55.38 mph (89.13 km/h) |
| 65 mph (104.61 km/h) | 60 mph (96.56 km/h) |
| 70 mph (112.65 km/h) | 64.61 mph (103.99 km/h) |
| 75 mph (120.7 km/h) | 69.23 mph (111.42 km/h) |
| 80 mph (128.75 km/h) | 73.85 mph (118.84 km/h) |
| 85 mph (136.79 km/h) | 78.46 mph (126.27 km/h) |
| 90 mph (144.84 km/h) | 83.08 mph (133.7 km/h) |
| 95 mph (152.89 km/h) | 87.69 mph (141.13 km/h) |
| 100 mph (160.93 km/h) | 92.31 mph (148.55 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1873 | 2176 | 2344 | 2447 | 2559 | 2639 | 2726 | 2830 | 2973 | 3117 | 3276 | 3404 | 3635 | 3890 | 4089 | 4217 | 4289 | 4552 | 4918 | 5716 |
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