245/55R19 vs 275/45R20
275/45R20 is a safe swap for 245/55R19 by the usual ±3% rule: the diameter differs by +0.45%.
Speedometer and odometer
With 275/45R20 on a car calibrated for 245/55R19, the speedometer reads 59.7 mph when you're really doing 60, and the odometer under-counts by 0.5%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 30.1 mph |
| 45 mph | 45.2 mph |
| 60 mph | 60.3 mph |
| 70 mph | 70.3 mph |
| 80 mph | 80.4 mph |
Other sizes close to 245/55R19
- 245/55R19 vs 235/55R19-1.46%
- 245/55R19 vs 255/50R19-1.93%
- 245/55R19 vs 245/60R18-0.12%
- 245/55R19 vs 245/50R20+0.12%
- 245/55R19 vs 225/55R19-2.93%
- 245/55R19 vs 235/50R19-4.59%
- 245/55R19 vs 255/55R19+1.46%
- 245/55R19 vs 265/45R20-0.74%
- 245/55R19 vs 255/60R19+4.85%
- 245/55R19 vs 265/50R19-0.60%
- 245/55R19 vs 245/50R19-3.26%
- 245/55R19 vs 275/55R19+4.39%
Questions
Can I replace 245/55R19 with 275/45R20?
275/45R20 is a safe swap for 245/55R19 by the usual ±3% rule: the diameter differs by +0.45%.
What's the difference between 245/55R19 and 275/45R20?
275/45R20 is 0.13" taller and 30 mm wider; the sidewall is -0.43". At an indicated 60 mph you'd actually be doing 60.3 mph.
Will 275/45R20 fit on 245/55R19 wheels?
No — 245/55R19 needs a 19" wheel and 275/45R20 a 20" wheel. This is a plus/minus-size swap that changes wheels too.