CarSpecsHQ

255/35R19 vs 225/40R19

225/40R19 is a safe swap for 255/35R19 by the usual ±3% rule: the diameter differs by +0.23%.

19" rim
255/35R19 26.03" · 225/40R19 26.09" · drawn to scale

Side by side

255/35R19225/40R19Difference
Overall diameter26.03"26.09"+0.06" (+0.23%)
Section width255 mm225 mm-30 mm
Sidewall3.51"3.54"+0.03"
Rim19"19"same
Circumference81.8"82.0"+0.2"
Revs per mile775773-2
Ride height——+0.03"
Speedometer reads 60 mph60.060.1+0.1 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.1 mph

With 225/40R19 on a car calibrated for 255/35R19, the speedometer reads 59.9 mph when you're really doing 60, and the odometer under-counts by 0.2%.

Speedo showsActual speed
30 mph30.1 mph
45 mph45.1 mph
60 mph60.1 mph
70 mph70.2 mph
80 mph80.2 mph

Other sizes close to 255/35R19

Questions

Can I replace 255/35R19 with 225/40R19?

225/40R19 is a safe swap for 255/35R19 by the usual ±3% rule: the diameter differs by +0.23%.

What's the difference between 255/35R19 and 225/40R19?

225/40R19 is 0.06" taller and 30 mm narrower; the sidewall is +0.03". At an indicated 60 mph you'd actually be doing 60.1 mph.

Will 225/40R19 fit on 255/35R19 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.