Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 120/70-21 | 130/80-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 27.61 (701.4) | 29.19 (741.4) | 1.57 (40) 5.7% |
| Width inches (mm) | 4.72 (120) | 5.12 (130) | 0.39 (10) 8.3% |
| Circum. inches (mm) | 86.75 (2203.51) | 91.7 (2329.18) | 4.95 (125.66) 5.7% |
| Sidewall Height inches (mm) | 3.31 (84) | 4.09 (104) | 0.79 (20) 23.8% |
| Revolutions per mile (km) | 730.35 (453.82) | 690.95 (429.34) | -39.4 (-24.48) -5.4% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.14 mph (34.02 km/h) |
| 25 mph (40.23 km/h) | 26.43 mph (42.53 km/h) |
| 30 mph (48.28 km/h) | 31.71 mph (51.03 km/h) |
| 35 mph (56.33 km/h) | 37 mph (59.54 km/h) |
| 40 mph (64.37 km/h) | 42.28 mph (68.05 km/h) |
| 45 mph (72.42 km/h) | 47.57 mph (76.55 km/h) |
| 50 mph (80.47 km/h) | 52.85 mph (85.06 km/h) |
| 55 mph (88.51 km/h) | 58.14 mph (93.56 km/h) |
| 60 mph (96.56 km/h) | 63.42 mph (102.07 km/h) |
| 65 mph (104.61 km/h) | 68.71 mph (110.57 km/h) |
| 70 mph (112.65 km/h) | 73.99 mph (119.08 km/h) |
| 75 mph (120.7 km/h) | 79.28 mph (127.58 km/h) |
| 80 mph (128.75 km/h) | 84.56 mph (136.09 km/h) |
| 85 mph (136.79 km/h) | 89.85 mph (144.6 km/h) |
| 90 mph (144.84 km/h) | 95.13 mph (153.1 km/h) |
| 95 mph (152.89 km/h) | 100.42 mph (161.61 km/h) |
| 100 mph (160.93 km/h) | 105.7 mph (170.11 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1758 | 2043 | 2200 | 2297 | 2402 | 2477 | 2559 | 2656 | 2791 | 2926 | 3075 | 3195 | 3412 | 3651 | 3838 | 3958 | 4025 | 4272 | 4617 | 5365 |
Better Fuel Economy Factory Ratios Increased Power
