Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/40-23 | 380/70-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 32.61 (828.2) | 40.94 (1040) | 8.34 (211.8) 25.6% |
| Width inches (mm) | 12.01 (305) | 14.96 (380) | 2.95 (75) 24.6% |
| Circum. inches (mm) | 102.44 (2601.87) | 128.63 (3267.26) | 26.2 (665.39) 25.6% |
| Sidewall Height inches (mm) | 4.8 (122) | 10.47 (266) | 5.67 (144) 118% |
| Revolutions per mile (km) | 618.53 (384.34) | 492.57 (306.07) | -125.97 (-78.27) -20.4% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 25.11 mph (40.42 km/h) |
| 25 mph (40.23 km/h) | 31.39 mph (50.52 km/h) |
| 30 mph (48.28 km/h) | 37.67 mph (60.63 km/h) |
| 35 mph (56.33 km/h) | 43.95 mph (70.73 km/h) |
| 40 mph (64.37 km/h) | 50.23 mph (80.84 km/h) |
| 45 mph (72.42 km/h) | 56.51 mph (90.94 km/h) |
| 50 mph (80.47 km/h) | 62.79 mph (101.05 km/h) |
| 55 mph (88.51 km/h) | 69.07 mph (111.15 km/h) |
| 60 mph (96.56 km/h) | 75.34 mph (121.25 km/h) |
| 65 mph (104.61 km/h) | 81.62 mph (131.36 km/h) |
| 70 mph (112.65 km/h) | 87.9 mph (141.46 km/h) |
| 75 mph (120.7 km/h) | 94.18 mph (151.57 km/h) |
| 80 mph (128.75 km/h) | 100.46 mph (161.67 km/h) |
| 85 mph (136.79 km/h) | 106.74 mph (171.78 km/h) |
| 90 mph (144.84 km/h) | 113.02 mph (181.88 km/h) |
| 95 mph (152.89 km/h) | 119.29 mph (191.99 km/h) |
| 100 mph (160.93 km/h) | 125.57 mph (202.09 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1253 | 1456 | 1568 | 1638 | 1712 | 1766 | 1824 | 1894 | 1990 | 2086 | 2192 | 2278 | 2432 | 2603 | 2736 | 2822 | 2870 | 3046 | 3291 | 3824 |
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