CarSpecsHQ

255/45R19 vs 265/50R19

265/50R19 is outside the ±3% rule as a replacement for 255/45R19: the diameter differs by +4.99%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

19" rim
255/45R19 28.04" · 265/50R19 29.43" · drawn to scale

Side by side

255/45R19265/50R19Difference
Overall diameter28.04"29.43"+1.40" (+4.99%)
Section width255 mm265 mm+10 mm
Sidewall4.52"5.22"+0.70"
Rim19"19"same
Circumference88.1"92.5"+4.4"
Revs per mile719685-34
Ride height——+0.70"
Speedometer reads 60 mph60.063.0+3.0 mph

Speedometer and odometer

020406080100120 reads 60 · actual 63.0 mph

With 265/50R19 on a car calibrated for 255/45R19, the speedometer reads 57.2 mph when you're really doing 60, and the odometer under-counts by 5.0%.

Speedo showsActual speed
30 mph31.5 mph
45 mph47.2 mph
60 mph63.0 mph
70 mph73.5 mph
80 mph84.0 mph

Other sizes close to 255/45R19

Questions

Can I replace 255/45R19 with 265/50R19?

265/50R19 is outside the ±3% rule as a replacement for 255/45R19: the diameter differs by +4.99%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 255/45R19 and 265/50R19?

265/50R19 is 1.40" taller and 10 mm wider; the sidewall is +0.70". At an indicated 60 mph you'd actually be doing 63.0 mph.

Will 265/50R19 fit on 255/45R19 wheels?

Both use a 19" rim, so the wheel diameter matches; check the wheel's width range for a 265 mm tire and the fender clearance.