Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 90/90-21 | 80/100-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 27.38 (695.4) | 27.3 (693.4) | -0.08 (-2) -0.3% |
| Width inches (mm) | 3.54 (90) | 3.15 (80) | -0.39 (-10) -11.1% |
| Circum. inches (mm) | 86.01 (2184.66) | 85.76 (2178.38) | -0.25 (-6.28) -0.3% |
| Sidewall Height inches (mm) | 3.19 (81) | 3.15 (80) | -0.04 (-1) -1.2% |
| Revolutions per mile (km) | 736.66 (457.74) | 738.78 (459.06) | 2.12 (1.32) 0.3% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.94 mph (32.09 km/h) |
| 25 mph (40.23 km/h) | 24.93 mph (40.12 km/h) |
| 30 mph (48.28 km/h) | 29.91 mph (48.14 km/h) |
| 35 mph (56.33 km/h) | 34.9 mph (56.17 km/h) |
| 40 mph (64.37 km/h) | 39.88 mph (64.19 km/h) |
| 45 mph (72.42 km/h) | 44.87 mph (72.21 km/h) |
| 50 mph (80.47 km/h) | 49.86 mph (80.24 km/h) |
| 55 mph (88.51 km/h) | 54.84 mph (88.26 km/h) |
| 60 mph (96.56 km/h) | 59.83 mph (96.28 km/h) |
| 65 mph (104.61 km/h) | 64.81 mph (104.31 km/h) |
| 70 mph (112.65 km/h) | 69.8 mph (112.33 km/h) |
| 75 mph (120.7 km/h) | 74.78 mph (120.35 km/h) |
| 80 mph (128.75 km/h) | 79.77 mph (128.38 km/h) |
| 85 mph (136.79 km/h) | 84.76 mph (136.4 km/h) |
| 90 mph (144.84 km/h) | 89.74 mph (144.42 km/h) |
| 95 mph (152.89 km/h) | 94.73 mph (152.45 km/h) |
| 100 mph (160.93 km/h) | 99.71 mph (160.47 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1880 | 2184 | 2352 | 2456 | 2568 | 2648 | 2736 | 2840 | 2984 | 3128 | 3288 | 3416 | 3648 | 3904 | 4104 | 4232 | 4304 | 4568 | 4936 | 5736 |
Better Fuel Economy Factory Ratios Increased Power
