CarSpecsHQ

305/40R22 vs 275/50R22

275/50R22 is outside the ±3% rule as a replacement for 305/40R22: the diameter differs by +3.86%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

22" rim
305/40R22 31.61" · 275/50R22 32.83" · drawn to scale

Side by side

305/40R22275/50R22Difference
Overall diameter31.61"32.83"+1.22" (+3.86%)
Section width305 mm275 mm-30 mm
Sidewall4.80"5.41"+0.61"
Rim22"22"same
Circumference99.3"103.1"+3.8"
Revs per mile638614-24
Ride height——+0.61"
Speedometer reads 60 mph60.062.3+2.3 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.3 mph

With 275/50R22 on a car calibrated for 305/40R22, the speedometer reads 57.8 mph when you're really doing 60, and the odometer under-counts by 3.9%.

Speedo showsActual speed
30 mph31.2 mph
45 mph46.7 mph
60 mph62.3 mph
70 mph72.7 mph
80 mph83.1 mph

Other sizes close to 305/40R22

Questions

Can I replace 305/40R22 with 275/50R22?

275/50R22 is outside the ±3% rule as a replacement for 305/40R22: the diameter differs by +3.86%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 305/40R22 and 275/50R22?

275/50R22 is 1.22" taller and 30 mm narrower; the sidewall is +0.61". At an indicated 60 mph you'd actually be doing 62.3 mph.

Will 275/50R22 fit on 305/40R22 wheels?

Both use a 22" rim, so the wheel diameter matches; check the wheel's width range for a 275 mm tire and the fender clearance.