255/60R18 vs 225/75R17
225/75R17 is a safe swap for 255/60R18 by the usual ±3% rule: the diameter differs by +0.80%.
Speedometer and odometer
With 225/75R17 on a car calibrated for 255/60R18, the speedometer reads 59.5 mph when you're really doing 60, and the odometer under-counts by 0.8%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 30.2 mph |
| 45 mph | 45.4 mph |
| 60 mph | 60.5 mph |
| 70 mph | 70.6 mph |
| 80 mph | 80.6 mph |
Other sizes close to 255/60R18
- 255/60R18 vs 235/60R18-3.14%
- 255/60R18 vs 265/60R18+1.57%
- 255/60R18 vs 225/60R18-4.72%
- 255/60R18 vs 245/60R18-1.57%
- 255/60R18 vs 255/55R18-3.34%
- 255/60R18 vs 235/65R18-0.07%
- 255/60R18 vs 255/65R18+3.34%
- 255/60R18 vs 255/55R19-0.01%
- 255/60R18 vs 255/65R17+0.01%
- 255/60R18 vs 245/55R18-4.78%
- 255/60R18 vs 285/60R18+4.72%
- 255/60R18 vs 235/70R17-0.31%
Questions
Can I replace 255/60R18 with 225/75R17?
225/75R17 is a safe swap for 255/60R18 by the usual ±3% rule: the diameter differs by +0.80%.
What's the difference between 255/60R18 and 225/75R17?
225/75R17 is 0.24" taller and 30 mm narrower; the sidewall is +0.62". At an indicated 60 mph you'd actually be doing 60.5 mph.
Will 225/75R17 fit on 255/60R18 wheels?
No — 255/60R18 needs a 18" wheel and 225/75R17 a 17" wheel. This is a plus/minus-size swap that changes wheels too.