CarSpecsHQ

285/30R19 vs 225/45R19

225/45R19 is outside the ±3% rule as a replacement for 285/30R19: the diameter differs by +4.82%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

19" rim
285/30R19 25.73" · 225/45R19 26.97" · drawn to scale

Side by side

285/30R19225/45R19Difference
Overall diameter25.73"26.97"+1.24" (+4.82%)
Section width285 mm225 mm-60 mm
Sidewall3.37"3.99"+0.62"
Rim19"19"same
Circumference80.8"84.7"+3.9"
Revs per mile784748-36
Ride height——+0.62"
Speedometer reads 60 mph60.062.9+2.9 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.9 mph

With 225/45R19 on a car calibrated for 285/30R19, the speedometer reads 57.2 mph when you're really doing 60, and the odometer under-counts by 4.8%.

Speedo showsActual speed
30 mph31.4 mph
45 mph47.2 mph
60 mph62.9 mph
70 mph73.4 mph
80 mph83.9 mph

Other sizes close to 285/30R19

Questions

Can I replace 285/30R19 with 225/45R19?

225/45R19 is outside the ±3% rule as a replacement for 285/30R19: the diameter differs by +4.82%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 285/30R19 and 225/45R19?

225/45R19 is 1.24" taller and 60 mm narrower; the sidewall is +0.62". At an indicated 60 mph you'd actually be doing 62.9 mph.

Will 225/45R19 fit on 285/30R19 wheels?

Both use a 19" rim, so the wheel diameter matches; check the wheel's width range for a 225 mm tire and the fender clearance.