CarSpecsHQ

275/45R19 vs 255/50R19

255/50R19 is a safe swap for 275/45R19 by the usual ±3% rule: the diameter differs by +1.03%.

19" rim
275/45R19 28.74" · 255/50R19 29.04" · drawn to scale

Side by side

275/45R19255/50R19Difference
Overall diameter28.74"29.04"+0.30" (+1.03%)
Section width275 mm255 mm-20 mm
Sidewall4.87"5.02"+0.15"
Rim19"19"same
Circumference90.3"91.2"+0.9"
Revs per mile702695-7
Ride height——+0.15"
Speedometer reads 60 mph60.060.6+0.6 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.6 mph

With 255/50R19 on a car calibrated for 275/45R19, the speedometer reads 59.4 mph when you're really doing 60, and the odometer under-counts by 1.0%.

Speedo showsActual speed
30 mph30.3 mph
45 mph45.5 mph
60 mph60.6 mph
70 mph70.7 mph
80 mph80.8 mph

Other sizes close to 275/45R19

Questions

Can I replace 275/45R19 with 255/50R19?

255/50R19 is a safe swap for 275/45R19 by the usual ±3% rule: the diameter differs by +1.03%.

What's the difference between 275/45R19 and 255/50R19?

255/50R19 is 0.30" taller and 20 mm narrower; the sidewall is +0.15". At an indicated 60 mph you'd actually be doing 60.6 mph.

Will 255/50R19 fit on 275/45R19 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.