Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 90/90-21 | 120/70-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 27.38 (695.4) | 27.61 (701.4) | 0.24 (6) 0.9% |
| Width inches (mm) | 3.54 (90) | 4.72 (120) | 1.18 (30) 33.3% |
| Circum. inches (mm) | 86.01 (2184.66) | 86.75 (2203.51) | 0.74 (18.85) 0.9% |
| Sidewall Height inches (mm) | 3.19 (81) | 3.31 (84) | 0.12 (3) 3.7% |
| Revolutions per mile (km) | 736.66 (457.74) | 730.35 (453.82) | -6.3 (-3.92) -0.9% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.17 mph (32.46 km/h) |
| 25 mph (40.23 km/h) | 25.22 mph (40.58 km/h) |
| 30 mph (48.28 km/h) | 30.26 mph (48.7 km/h) |
| 35 mph (56.33 km/h) | 35.3 mph (56.81 km/h) |
| 40 mph (64.37 km/h) | 40.35 mph (64.93 km/h) |
| 45 mph (72.42 km/h) | 45.39 mph (73.05 km/h) |
| 50 mph (80.47 km/h) | 50.43 mph (81.16 km/h) |
| 55 mph (88.51 km/h) | 55.47 mph (89.28 km/h) |
| 60 mph (96.56 km/h) | 60.52 mph (97.39 km/h) |
| 65 mph (104.61 km/h) | 65.56 mph (105.51 km/h) |
| 70 mph (112.65 km/h) | 70.6 mph (113.63 km/h) |
| 75 mph (120.7 km/h) | 75.65 mph (121.74 km/h) |
| 80 mph (128.75 km/h) | 80.69 mph (129.86 km/h) |
| 85 mph (136.79 km/h) | 85.73 mph (137.97 km/h) |
| 90 mph (144.84 km/h) | 90.78 mph (146.09 km/h) |
| 95 mph (152.89 km/h) | 95.82 mph (154.21 km/h) |
| 100 mph (160.93 km/h) | 100.86 mph (162.32 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1859 | 2159 | 2325 | 2428 | 2539 | 2618 | 2705 | 2808 | 2950 | 3092 | 3251 | 3377 | 3606 | 3860 | 4057 | 4184 | 4255 | 4516 | 4880 | 5671 |
Better Fuel Economy Factory Ratios Increased Power
