Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 355/25-21 | 325/30-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 27.99 (710.9) | 28.68 (728.4) | 0.69 (17.5) 2.5% |
| Width inches (mm) | 13.98 (355) | 12.8 (325) | -1.18 (-30) -8.5% |
| Circum. inches (mm) | 87.93 (2233.36) | 90.09 (2288.34) | 2.16 (54.98) 2.5% |
| Sidewall Height inches (mm) | 3.49 (88.75) | 3.84 (97.5) | 0.34 (8.75) 9.9% |
| Revolutions per mile (km) | 720.59 (447.76) | 703.28 (437) | -17.31 (-10.76) -2.4% |
325/30-21 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.49 mph (32.98 km/h) |
| 25 mph (40.23 km/h) | 25.62 mph (41.22 km/h) |
| 30 mph (48.28 km/h) | 30.74 mph (49.47 km/h) |
| 35 mph (56.33 km/h) | 35.86 mph (57.71 km/h) |
| 40 mph (64.37 km/h) | 40.98 mph (65.96 km/h) |
| 45 mph (72.42 km/h) | 46.11 mph (74.2 km/h) |
| 50 mph (80.47 km/h) | 51.23 mph (82.45 km/h) |
| 55 mph (88.51 km/h) | 56.35 mph (90.69 km/h) |
| 60 mph (96.56 km/h) | 61.48 mph (98.94 km/h) |
| 65 mph (104.61 km/h) | 66.6 mph (107.18 km/h) |
| 70 mph (112.65 km/h) | 71.72 mph (115.43 km/h) |
| 75 mph (120.7 km/h) | 76.85 mph (123.67 km/h) |
| 80 mph (128.75 km/h) | 81.97 mph (131.92 km/h) |
| 85 mph (136.79 km/h) | 87.09 mph (140.16 km/h) |
| 90 mph (144.84 km/h) | 92.22 mph (148.41 km/h) |
| 95 mph (152.89 km/h) | 97.34 mph (156.65 km/h) |
| 100 mph (160.93 km/h) | 102.46 mph (164.9 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1790 | 2079 | 2239 | 2338 | 2445 | 2521 | 2605 | 2704 | 2841 | 2978 | 3130 | 3252 | 3473 | 3717 | 3907 | 4029 | 4097 | 4349 | 4699 | 5461 |
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