Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 395/85-20 | 31/10.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 46.44 (1179.5) | 30.93 (785.68) | -15.5 (-393.82) -33.4% |
| Width inches (mm) | 15.55 (395) | 10.51 (267) | -5.04 (-128) -32.4% |
| Circum. inches (mm) | 145.89 (3705.51) | 97.18 (2468.29) | -48.71 (-1237.22) -33.4% |
| Sidewall Height inches (mm) | 13.22 (335.75) | 5.47 (138.84) | -7.75 (-196.91) -58.6% |
| Revolutions per mile (km) | 434.31 (269.87) | 652.01 (405.14) | 217.7 (135.27) 50.1% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 13.32 mph (21.44 km/h) |
| 25 mph (40.23 km/h) | 16.65 mph (26.8 km/h) |
| 30 mph (48.28 km/h) | 19.98 mph (32.16 km/h) |
| 35 mph (56.33 km/h) | 23.31 mph (37.52 km/h) |
| 40 mph (64.37 km/h) | 26.64 mph (42.88 km/h) |
| 45 mph (72.42 km/h) | 29.98 mph (48.24 km/h) |
| 50 mph (80.47 km/h) | 33.31 mph (53.6 km/h) |
| 55 mph (88.51 km/h) | 36.64 mph (58.96 km/h) |
| 60 mph (96.56 km/h) | 39.97 mph (64.32 km/h) |
| 65 mph (104.61 km/h) | 43.3 mph (69.68 km/h) |
| 70 mph (112.65 km/h) | 46.63 mph (75.04 km/h) |
| 75 mph (120.7 km/h) | 49.96 mph (80.4 km/h) |
| 80 mph (128.75 km/h) | 53.29 mph (85.76 km/h) |
| 85 mph (136.79 km/h) | 56.62 mph (91.12 km/h) |
| 90 mph (144.84 km/h) | 59.95 mph (96.48 km/h) |
| 95 mph (152.89 km/h) | 63.28 mph (101.84 km/h) |
| 100 mph (160.93 km/h) | 66.61 mph (107.2 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1659 | 1928 | 2076 | 2168 | 2266 | 2337 | 2415 | 2507 | 2634 | 2761 | 2902 | 3015 | 3220 | 3446 | 3622 | 3735 | 3799 | 4032 | 4356 | 5062 |
Better Fuel Economy Factory Ratios Increased Power
