245/45R19 vs 255/45R19
255/45R19 is a safe swap for 245/45R19 by the usual ±3% rule: the diameter differs by +1.28%.
Speedometer and odometer
With 255/45R19 on a car calibrated for 245/45R19, the speedometer reads 59.2 mph when you're really doing 60, and the odometer under-counts by 1.3%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 30.4 mph |
| 45 mph | 45.6 mph |
| 60 mph | 60.8 mph |
| 70 mph | 70.9 mph |
| 80 mph | 81.0 mph |
Other sizes close to 245/45R19
- 245/45R19 vs 245/40R19-3.48%
- 245/45R19 vs 255/50R19+4.91%
- 245/45R19 vs 235/40R19-4.62%
- 245/45R19 vs 255/40R19-2.35%
- 245/45R19 vs 225/55R18+0.23%
- 245/45R19 vs 245/40R20+0.13%
- 245/45R19 vs 275/35R19-3.98%
- 245/45R19 vs 225/55R19+3.84%
- 245/45R19 vs 275/40R19-0.07%
- 245/45R19 vs 275/35R20-0.37%
- 245/45R19 vs 225/45R19-2.56%
- 245/45R19 vs 245/50R18-0.13%
Questions
Can I replace 245/45R19 with 255/45R19?
255/45R19 is a safe swap for 245/45R19 by the usual ±3% rule: the diameter differs by +1.28%.
What's the difference between 245/45R19 and 255/45R19?
255/45R19 is 0.35" taller and 10 mm wider; the sidewall is +0.18". At an indicated 60 mph you'd actually be doing 60.8 mph.
Will 255/45R19 fit on 245/45R19 wheels?
Both use a 19" rim, so the wheel diameter matches; check the wheel's width range for a 255 mm tire and the fender clearance.