Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/30-21 | 275/30-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.68 (728.4) | 26.5 (673) | -2.18 (-55.4) -7.6% |
| Width inches (mm) | 12.8 (325) | 10.83 (275) | -1.97 (-50) -15.4% |
| Circum. inches (mm) | 90.09 (2288.34) | 83.24 (2114.29) | -6.85 (-174.04) -7.6% |
| Sidewall Height inches (mm) | 3.84 (97.5) | 3.25 (82.5) | -0.59 (-15) -15.4% |
| Revolutions per mile (km) | 703.28 (437) | 761.17 (472.97) | 57.89 (35.97) 8.2% |
275/30-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 18.48 mph (29.74 km/h) |
| 25 mph (40.23 km/h) | 23.1 mph (37.17 km/h) |
| 30 mph (48.28 km/h) | 27.72 mph (44.61 km/h) |
| 35 mph (56.33 km/h) | 32.34 mph (52.04 km/h) |
| 40 mph (64.37 km/h) | 36.96 mph (59.48 km/h) |
| 45 mph (72.42 km/h) | 41.58 mph (66.91 km/h) |
| 50 mph (80.47 km/h) | 46.2 mph (74.35 km/h) |
| 55 mph (88.51 km/h) | 50.82 mph (81.78 km/h) |
| 60 mph (96.56 km/h) | 55.44 mph (89.22 km/h) |
| 65 mph (104.61 km/h) | 60.06 mph (96.65 km/h) |
| 70 mph (112.65 km/h) | 64.68 mph (104.09 km/h) |
| 75 mph (120.7 km/h) | 69.3 mph (111.52 km/h) |
| 80 mph (128.75 km/h) | 73.92 mph (118.96 km/h) |
| 85 mph (136.79 km/h) | 78.54 mph (126.39 km/h) |
| 90 mph (144.84 km/h) | 83.15 mph (133.83 km/h) |
| 95 mph (152.89 km/h) | 87.77 mph (141.26 km/h) |
| 100 mph (160.93 km/h) | 92.39 mph (148.69 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1937 | 2250 | 2423 | 2531 | 2646 | 2728 | 2819 | 2926 | 3075 | 3223 | 3388 | 3520 | 3759 | 4022 | 4229 | 4360 | 4435 | 4707 | 5086 | 5910 |
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