CarSpecsHQ

235/40R19 vs 275/40R19

275/40R19 is outside the ±3% rule as a replacement for 235/40R19: the diameter differs by +4.77%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

19" rim
235/40R19 26.40" · 275/40R19 27.66" · drawn to scale

Side by side

235/40R19275/40R19Difference
Overall diameter26.40"27.66"+1.26" (+4.77%)
Section width235 mm275 mm+40 mm
Sidewall3.70"4.33"+0.63"
Rim19"19"same
Circumference82.9"86.9"+4.0"
Revs per mile764729-35
Ride height——+0.63"
Speedometer reads 60 mph60.062.9+2.9 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.9 mph

With 275/40R19 on a car calibrated for 235/40R19, the speedometer reads 57.3 mph when you're really doing 60, and the odometer under-counts by 4.8%.

Speedo showsActual speed
30 mph31.4 mph
45 mph47.1 mph
60 mph62.9 mph
70 mph73.3 mph
80 mph83.8 mph

Other sizes close to 235/40R19

Questions

Can I replace 235/40R19 with 275/40R19?

275/40R19 is outside the ±3% rule as a replacement for 235/40R19: the diameter differs by +4.77%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 235/40R19 and 275/40R19?

275/40R19 is 1.26" taller and 40 mm wider; the sidewall is +0.63". At an indicated 60 mph you'd actually be doing 62.9 mph.

Will 275/40R19 fit on 235/40R19 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.