Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 100/90-21 | 90/80-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.09 (713.4) | 26.67 (677.4) | -1.42 (-36) -5% |
| Width inches (mm) | 3.94 (100) | 3.54 (90) | -0.39 (-10) -10% |
| Circum. inches (mm) | 88.24 (2241.21) | 83.78 (2128.11) | -4.45 (-113.1) -5% |
| Sidewall Height inches (mm) | 3.54 (90) | 2.83 (72) | -0.71 (-18) -20% |
| Revolutions per mile (km) | 718.07 (446.19) | 756.23 (469.9) | 38.16 (23.71) 5.3% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 18.99 mph (30.56 km/h) |
| 25 mph (40.23 km/h) | 23.74 mph (38.2 km/h) |
| 30 mph (48.28 km/h) | 28.49 mph (45.84 km/h) |
| 35 mph (56.33 km/h) | 33.23 mph (53.48 km/h) |
| 40 mph (64.37 km/h) | 37.98 mph (61.13 km/h) |
| 45 mph (72.42 km/h) | 42.73 mph (68.77 km/h) |
| 50 mph (80.47 km/h) | 47.48 mph (76.41 km/h) |
| 55 mph (88.51 km/h) | 52.22 mph (84.05 km/h) |
| 60 mph (96.56 km/h) | 56.97 mph (91.69 km/h) |
| 65 mph (104.61 km/h) | 61.72 mph (99.33 km/h) |
| 70 mph (112.65 km/h) | 66.47 mph (106.97 km/h) |
| 75 mph (120.7 km/h) | 71.22 mph (114.61 km/h) |
| 80 mph (128.75 km/h) | 75.96 mph (122.25 km/h) |
| 85 mph (136.79 km/h) | 80.71 mph (129.89 km/h) |
| 90 mph (144.84 km/h) | 85.46 mph (137.53 km/h) |
| 95 mph (152.89 km/h) | 90.21 mph (145.17 km/h) |
| 100 mph (160.93 km/h) | 94.95 mph (152.81 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1924 | 2236 | 2408 | 2514 | 2629 | 2711 | 2801 | 2907 | 3055 | 3202 | 3366 | 3497 | 3734 | 3996 | 4201 | 4332 | 4406 | 4676 | 5053 | 5872 |
Better Fuel Economy Factory Ratios Increased Power
