Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 275/55-21 | 285/55-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 32.91 (835.9) | 32.34 (821.5) | -0.57 (-14.4) -1.7% |
| Width inches (mm) | 10.83 (275) | 11.22 (285) | 0.39 (10) 3.6% |
| Circum. inches (mm) | 103.39 (2626.06) | 101.61 (2580.82) | -1.78 (-45.24) -1.7% |
| Sidewall Height inches (mm) | 5.95 (151.25) | 6.17 (156.75) | 0.22 (5.5) 3.6% |
| Revolutions per mile (km) | 612.84 (380.8) | 623.58 (387.47) | 10.74 (6.67) 1.8% |
285/55-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.66 mph (31.63 km/h) |
| 25 mph (40.23 km/h) | 24.57 mph (39.54 km/h) |
| 30 mph (48.28 km/h) | 29.48 mph (47.45 km/h) |
| 35 mph (56.33 km/h) | 34.4 mph (55.36 km/h) |
| 40 mph (64.37 km/h) | 39.31 mph (63.26 km/h) |
| 45 mph (72.42 km/h) | 44.22 mph (71.17 km/h) |
| 50 mph (80.47 km/h) | 49.14 mph (79.08 km/h) |
| 55 mph (88.51 km/h) | 54.05 mph (86.99 km/h) |
| 60 mph (96.56 km/h) | 58.97 mph (94.9 km/h) |
| 65 mph (104.61 km/h) | 63.88 mph (102.81 km/h) |
| 70 mph (112.65 km/h) | 68.79 mph (110.71 km/h) |
| 75 mph (120.7 km/h) | 73.71 mph (118.62 km/h) |
| 80 mph (128.75 km/h) | 78.62 mph (126.53 km/h) |
| 85 mph (136.79 km/h) | 83.54 mph (134.44 km/h) |
| 90 mph (144.84 km/h) | 88.45 mph (142.35 km/h) |
| 95 mph (152.89 km/h) | 93.36 mph (150.25 km/h) |
| 100 mph (160.93 km/h) | 98.28 mph (158.16 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1587 | 1843 | 1985 | 2073 | 2168 | 2235 | 2309 | 2397 | 2519 | 2640 | 2775 | 2883 | 3079 | 3295 | 3464 | 3572 | 3633 | 3856 | 4166 | 4842 |
Better Fuel Economy Factory Ratios Increased Power
