CarSpecsHQ

225/45R19 vs 285/40R19

285/40R19 is outside the ±3% rule as a replacement for 225/45R19: the diameter differs by +3.72%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

19" rim
225/45R19 26.97" · 285/40R19 27.98" · drawn to scale

Side by side

225/45R19285/40R19Difference
Overall diameter26.97"27.98"+1.00" (+3.72%)
Section width225 mm285 mm+60 mm
Sidewall3.99"4.49"+0.50"
Rim19"19"same
Circumference84.7"87.9"+3.2"
Revs per mile748721-27
Ride height——+0.50"
Speedometer reads 60 mph60.062.2+2.2 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.2 mph

With 285/40R19 on a car calibrated for 225/45R19, the speedometer reads 57.8 mph when you're really doing 60, and the odometer under-counts by 3.7%.

Speedo showsActual speed
30 mph31.1 mph
45 mph46.7 mph
60 mph62.2 mph
70 mph72.6 mph
80 mph83.0 mph

Other sizes close to 225/45R19

Questions

Can I replace 225/45R19 with 285/40R19?

285/40R19 is outside the ±3% rule as a replacement for 225/45R19: the diameter differs by +3.72%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 225/45R19 and 285/40R19?

285/40R19 is 1.00" taller and 60 mm wider; the sidewall is +0.50". At an indicated 60 mph you'd actually be doing 62.2 mph.

Will 285/40R19 fit on 225/45R19 wheels?

Both use a 19" rim, so the wheel diameter matches; check the wheel's width range for a 285 mm tire and the fender clearance.