Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/25-21 | 275/30-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 27 (685.9) | 26.5 (673) | -0.51 (-12.9) -1.9% |
| Width inches (mm) | 12.01 (305) | 10.83 (275) | -1.18 (-30) -9.8% |
| Circum. inches (mm) | 84.84 (2154.82) | 83.24 (2114.29) | -1.6 (-40.53) -1.9% |
| Sidewall Height inches (mm) | 3 (76.25) | 3.25 (82.5) | 0.25 (6.25) 8.2% |
| Revolutions per mile (km) | 746.86 (464.08) | 761.17 (472.97) | 14.32 (8.9) 1.9% |
275/30-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.62 mph (31.58 km/h) |
| 25 mph (40.23 km/h) | 24.53 mph (39.48 km/h) |
| 30 mph (48.28 km/h) | 29.44 mph (47.37 km/h) |
| 35 mph (56.33 km/h) | 34.34 mph (55.27 km/h) |
| 40 mph (64.37 km/h) | 39.25 mph (63.16 km/h) |
| 45 mph (72.42 km/h) | 44.15 mph (71.06 km/h) |
| 50 mph (80.47 km/h) | 49.06 mph (78.95 km/h) |
| 55 mph (88.51 km/h) | 53.97 mph (86.85 km/h) |
| 60 mph (96.56 km/h) | 58.87 mph (94.74 km/h) |
| 65 mph (104.61 km/h) | 63.78 mph (102.64 km/h) |
| 70 mph (112.65 km/h) | 68.68 mph (110.54 km/h) |
| 75 mph (120.7 km/h) | 73.59 mph (118.43 km/h) |
| 80 mph (128.75 km/h) | 78.5 mph (126.33 km/h) |
| 85 mph (136.79 km/h) | 83.4 mph (134.22 km/h) |
| 90 mph (144.84 km/h) | 88.31 mph (142.12 km/h) |
| 95 mph (152.89 km/h) | 93.21 mph (150.01 km/h) |
| 100 mph (160.93 km/h) | 98.12 mph (157.91 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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