CarSpecsHQ

235/35R19 vs 235/40R19

235/40R19 is outside the ±3% rule as a replacement for 235/35R19: the diameter differs by +3.63%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

19" rim
235/35R19 25.48" · 235/40R19 26.40" · drawn to scale

Side by side

235/35R19235/40R19Difference
Overall diameter25.48"26.40"+0.93" (+3.63%)
Section width235 mm235 mm0 mm
Sidewall3.24"3.70"+0.46"
Rim19"19"same
Circumference80.0"82.9"+2.9"
Revs per mile792764-28
Ride height——+0.46"
Speedometer reads 60 mph60.062.2+2.2 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.2 mph

With 235/40R19 on a car calibrated for 235/35R19, the speedometer reads 57.9 mph when you're really doing 60, and the odometer under-counts by 3.6%.

Speedo showsActual speed
30 mph31.1 mph
45 mph46.6 mph
60 mph62.2 mph
70 mph72.5 mph
80 mph82.9 mph

Other sizes close to 235/35R19

Questions

Can I replace 235/35R19 with 235/40R19?

235/40R19 is outside the ±3% rule as a replacement for 235/35R19: the diameter differs by +3.63%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 235/35R19 and 235/40R19?

235/40R19 is 0.93" taller and 0 mm wider; the sidewall is +0.46". At an indicated 60 mph you'd actually be doing 62.2 mph.

Will 235/40R19 fit on 235/35R19 wheels?

Both use a 19" rim, so the wheel diameter matches; check the wheel's width range for a 235 mm tire and the fender clearance.