Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 235/45-20 | 275/45-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.33 (719.5) | 30.74 (780.9) | 2.42 (61.4) 8.5% |
| Width inches (mm) | 9.25 (235) | 10.83 (275) | 1.57 (40) 17% |
| Circum. inches (mm) | 88.99 (2260.38) | 96.59 (2453.27) | 7.59 (192.89) 8.5% |
| Sidewall Height inches (mm) | 4.16 (105.75) | 4.87 (123.75) | 0.71 (18) 17% |
| Revolutions per mile (km) | 711.98 (442.4) | 656 (407.62) | -55.98 (-34.78) -7.9% |
275/45-21 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.71 mph (34.93 km/h) |
| 25 mph (40.23 km/h) | 27.13 mph (43.67 km/h) |
| 30 mph (48.28 km/h) | 32.56 mph (52.4 km/h) |
| 35 mph (56.33 km/h) | 37.99 mph (61.13 km/h) |
| 40 mph (64.37 km/h) | 43.41 mph (69.87 km/h) |
| 45 mph (72.42 km/h) | 48.84 mph (78.6 km/h) |
| 50 mph (80.47 km/h) | 54.27 mph (87.33 km/h) |
| 55 mph (88.51 km/h) | 59.69 mph (96.07 km/h) |
| 60 mph (96.56 km/h) | 65.12 mph (104.8 km/h) |
| 65 mph (104.61 km/h) | 70.55 mph (113.53 km/h) |
| 70 mph (112.65 km/h) | 75.97 mph (122.27 km/h) |
| 75 mph (120.7 km/h) | 81.4 mph (131 km/h) |
| 80 mph (128.75 km/h) | 86.83 mph (139.73 km/h) |
| 85 mph (136.79 km/h) | 92.25 mph (148.47 km/h) |
| 90 mph (144.84 km/h) | 97.68 mph (157.2 km/h) |
| 95 mph (152.89 km/h) | 103.11 mph (165.93 km/h) |
| 100 mph (160.93 km/h) | 108.53 mph (174.67 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1669 | 1939 | 2089 | 2181 | 2280 | 2351 | 2430 | 2522 | 2650 | 2778 | 2920 | 3033 | 3239 | 3467 | 3644 | 3758 | 3822 | 4056 | 4383 | 5093 |
Better Fuel Economy Factory Ratios Increased Power
