Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 40/12.5-20 | 305/50-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 40.03 (1016.8) | 32.01 (813) | -8.02 (-203.8) -20% |
| Width inches (mm) | 12.52 (318) | 12.01 (305) | -0.51 (-13) -4.1% |
| Circum. inches (mm) | 125.76 (3194.37) | 100.56 (2554.11) | -25.21 (-640.26) -20% |
| Sidewall Height inches (mm) | 10.02 (254.4) | 6 (152.5) | -4.01 (-101.9) -40.1% |
| Revolutions per mile (km) | 503.81 (313.05) | 630.1 (391.52) | 126.29 (78.47) 25.1% |
305/50-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 15.99 mph (25.74 km/h) |
| 25 mph (40.23 km/h) | 19.99 mph (32.17 km/h) |
| 30 mph (48.28 km/h) | 23.99 mph (38.6 km/h) |
| 35 mph (56.33 km/h) | 27.98 mph (45.04 km/h) |
| 40 mph (64.37 km/h) | 31.98 mph (51.47 km/h) |
| 45 mph (72.42 km/h) | 35.98 mph (57.91 km/h) |
| 50 mph (80.47 km/h) | 39.98 mph (64.34 km/h) |
| 55 mph (88.51 km/h) | 43.98 mph (70.77 km/h) |
| 60 mph (96.56 km/h) | 47.97 mph (77.21 km/h) |
| 65 mph (104.61 km/h) | 51.97 mph (83.64 km/h) |
| 70 mph (112.65 km/h) | 55.97 mph (90.07 km/h) |
| 75 mph (120.7 km/h) | 59.97 mph (96.51 km/h) |
| 80 mph (128.75 km/h) | 63.97 mph (102.94 km/h) |
| 85 mph (136.79 km/h) | 67.96 mph (109.38 km/h) |
| 90 mph (144.84 km/h) | 71.96 mph (115.81 km/h) |
| 95 mph (152.89 km/h) | 75.96 mph (122.24 km/h) |
| 100 mph (160.93 km/h) | 79.96 mph (128.68 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1603 | 1863 | 2006 | 2095 | 2190 | 2259 | 2334 | 2422 | 2545 | 2668 | 2804 | 2914 | 3111 | 3330 | 3500 | 3610 | 3671 | 3896 | 4210 | 4892 |
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