Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 38/13.5-20 | 305/70-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 38.1 (967.62) | 34.81 (884.2) | -3.28 (-83.42) -8.6% |
| Width inches (mm) | 13.5 (343) | 12.01 (305) | -1.5 (-38) -11.1% |
| Circum. inches (mm) | 119.68 (3039.87) | 109.36 (2777.8) | -10.32 (-262.07) -8.6% |
| Sidewall Height inches (mm) | 9.05 (229.81) | 8.41 (213.5) | -0.64 (-16.31) -7.1% |
| Revolutions per mile (km) | 529.41 (328.96) | 579.36 (360) | 49.95 (31.04) 9.4% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 18.28 mph (29.41 km/h) |
| 25 mph (40.23 km/h) | 22.84 mph (36.77 km/h) |
| 30 mph (48.28 km/h) | 27.41 mph (44.12 km/h) |
| 35 mph (56.33 km/h) | 31.98 mph (51.47 km/h) |
| 40 mph (64.37 km/h) | 36.55 mph (58.82 km/h) |
| 45 mph (72.42 km/h) | 41.12 mph (66.18 km/h) |
| 50 mph (80.47 km/h) | 45.69 mph (73.53 km/h) |
| 55 mph (88.51 km/h) | 50.26 mph (80.88 km/h) |
| 60 mph (96.56 km/h) | 54.83 mph (88.24 km/h) |
| 65 mph (104.61 km/h) | 59.4 mph (95.59 km/h) |
| 70 mph (112.65 km/h) | 63.97 mph (102.94 km/h) |
| 75 mph (120.7 km/h) | 68.53 mph (110.3 km/h) |
| 80 mph (128.75 km/h) | 73.1 mph (117.65 km/h) |
| 85 mph (136.79 km/h) | 77.67 mph (125 km/h) |
| 90 mph (144.84 km/h) | 82.24 mph (132.35 km/h) |
| 95 mph (152.89 km/h) | 86.81 mph (139.71 km/h) |
| 100 mph (160.93 km/h) | 91.38 mph (147.06 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1474 | 1713 | 1845 | 1926 | 2014 | 2077 | 2146 | 2227 | 2340 | 2453 | 2579 | 2679 | 2861 | 3062 | 3218 | 3319 | 3375 | 3582 | 3871 | 4498 |
Better Fuel Economy Factory Ratios Increased Power
