Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 100/90-21 | 120/90-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.09 (713.4) | 29.5 (749.4) | 1.42 (36) 5% |
| Width inches (mm) | 3.94 (100) | 4.72 (120) | 0.79 (20) 20% |
| Circum. inches (mm) | 88.24 (2241.21) | 92.69 (2354.31) | 4.45 (113.1) 5% |
| Sidewall Height inches (mm) | 3.54 (90) | 4.25 (108) | 0.71 (18) 20% |
| Revolutions per mile (km) | 718.07 (446.19) | 683.57 (424.75) | -34.49 (-21.43) -4.8% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.01 mph (33.81 km/h) |
| 25 mph (40.23 km/h) | 26.26 mph (42.26 km/h) |
| 30 mph (48.28 km/h) | 31.51 mph (50.72 km/h) |
| 35 mph (56.33 km/h) | 36.77 mph (59.17 km/h) |
| 40 mph (64.37 km/h) | 42.02 mph (67.62 km/h) |
| 45 mph (72.42 km/h) | 47.27 mph (76.08 km/h) |
| 50 mph (80.47 km/h) | 52.52 mph (84.53 km/h) |
| 55 mph (88.51 km/h) | 57.78 mph (92.98 km/h) |
| 60 mph (96.56 km/h) | 63.03 mph (101.43 km/h) |
| 65 mph (104.61 km/h) | 68.28 mph (109.89 km/h) |
| 70 mph (112.65 km/h) | 73.53 mph (118.34 km/h) |
| 75 mph (120.7 km/h) | 78.78 mph (126.79 km/h) |
| 80 mph (128.75 km/h) | 84.04 mph (135.24 km/h) |
| 85 mph (136.79 km/h) | 89.29 mph (143.7 km/h) |
| 90 mph (144.84 km/h) | 94.54 mph (152.15 km/h) |
| 95 mph (152.89 km/h) | 99.79 mph (160.6 km/h) |
| 100 mph (160.93 km/h) | 105.05 mph (169.06 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1740 | 2021 | 2176 | 2273 | 2376 | 2450 | 2532 | 2628 | 2761 | 2894 | 3042 | 3161 | 3375 | 3612 | 3797 | 3916 | 3982 | 4227 | 4567 | 5308 |
Better Fuel Economy Factory Ratios Increased Power
