CarSpecsHQ

255/45R19 vs 235/55R19

235/55R19 is outside the ±3% rule as a replacement for 255/45R19: the diameter differs by +4.07%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

19" rim
255/45R19 28.04" · 235/55R19 29.18" · drawn to scale

Side by side

255/45R19235/55R19Difference
Overall diameter28.04"29.18"+1.14" (+4.07%)
Section width255 mm235 mm-20 mm
Sidewall4.52"5.09"+0.57"
Rim19"19"same
Circumference88.1"91.7"+3.6"
Revs per mile719691-28
Ride height——+0.57"
Speedometer reads 60 mph60.062.4+2.4 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.4 mph

With 235/55R19 on a car calibrated for 255/45R19, the speedometer reads 57.7 mph when you're really doing 60, and the odometer under-counts by 4.1%.

Speedo showsActual speed
30 mph31.2 mph
45 mph46.8 mph
60 mph62.4 mph
70 mph72.9 mph
80 mph83.3 mph

Other sizes close to 255/45R19

Questions

Can I replace 255/45R19 with 235/55R19?

235/55R19 is outside the ±3% rule as a replacement for 255/45R19: the diameter differs by +4.07%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 255/45R19 and 235/55R19?

235/55R19 is 1.14" taller and 20 mm narrower; the sidewall is +0.57". At an indicated 60 mph you'd actually be doing 62.4 mph.

Will 235/55R19 fit on 255/45R19 wheels?

Both use a 19" rim, so the wheel diameter matches; check the wheel's width range for a 235 mm tire and the fender clearance.