CarSpecsHQ

225/45R19 vs 275/40R19

275/40R19 is a safe swap for 225/45R19 by the usual ±3% rule: the diameter differs by +2.55%.

19" rim
225/45R19 26.97" · 275/40R19 27.66" · drawn to scale

Side by side

225/45R19275/40R19Difference
Overall diameter26.97"27.66"+0.69" (+2.55%)
Section width225 mm275 mm+50 mm
Sidewall3.99"4.33"+0.34"
Rim19"19"same
Circumference84.7"86.9"+2.2"
Revs per mile748729-19
Ride height——+0.34"
Speedometer reads 60 mph60.061.5+1.5 mph

Speedometer and odometer

020406080100120 reads 60 · actual 61.5 mph

With 275/40R19 on a car calibrated for 225/45R19, the speedometer reads 58.5 mph when you're really doing 60, and the odometer under-counts by 2.6%.

Speedo showsActual speed
30 mph30.8 mph
45 mph46.1 mph
60 mph61.5 mph
70 mph71.8 mph
80 mph82.0 mph

Other sizes close to 225/45R19

Questions

Can I replace 225/45R19 with 275/40R19?

275/40R19 is a safe swap for 225/45R19 by the usual ±3% rule: the diameter differs by +2.55%.

What's the difference between 225/45R19 and 275/40R19?

275/40R19 is 0.69" taller and 50 mm wider; the sidewall is +0.34". At an indicated 60 mph you'd actually be doing 61.5 mph.

Will 275/40R19 fit on 225/45R19 wheels?

Both use a 19" rim, so the wheel diameter matches; check the wheel's width range for a 275 mm tire and the fender clearance.