225/55R18 vs 275/45R18
275/45R18 is a safe swap for 225/55R18 by the usual ±3% rule: the diameter differs by 0.00%.
Speedometer and odometer
With 275/45R18 on a car calibrated for 225/55R18, the speedometer reads 60.0 mph when you're really doing 60, and the odometer over-counts by 0.0%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 30.0 mph |
| 45 mph | 45.0 mph |
| 60 mph | 60.0 mph |
| 70 mph | 70.0 mph |
| 80 mph | 80.0 mph |
Other sizes close to 225/55R18
- 225/55R18 vs 235/60R18+4.90%
- 225/55R18 vs 245/45R18-3.83%
- 225/55R18 vs 235/50R18-1.77%
- 225/55R18 vs 235/55R18+1.56%
- 225/55R18 vs 245/45R19-0.23%
- 225/55R18 vs 225/60R18+3.19%
- 225/55R18 vs 225/50R18-3.19%
- 225/55R18 vs 225/60R17-0.41%
- 225/55R18 vs 255/55R18+4.68%
- 225/55R18 vs 275/40R19-0.30%
- 225/55R18 vs 215/65R17+0.94%
- 225/55R18 vs 245/50R18-0.35%
Questions
Can I replace 225/55R18 with 275/45R18?
275/45R18 is a safe swap for 225/55R18 by the usual ±3% rule: the diameter differs by 0.00%.
What's the difference between 225/55R18 and 275/45R18?
275/45R18 is 0.00" taller and 50 mm wider; the sidewall is 0.00". At an indicated 60 mph you'd actually be doing 60.0 mph.
Will 275/45R18 fit on 225/55R18 wheels?
Both use a 18" rim, so the wheel diameter matches; check the wheel's width range for a 275 mm tire and the fender clearance.