CarSpecsHQ

325/35R22 vs 285/40R22

285/40R22 is a safe swap for 325/35R22 by the usual ±3% rule: the diameter differs by +0.06%.

22" rim
325/35R22 30.96" · 285/40R22 30.98" · drawn to scale

Side by side

325/35R22285/40R22Difference
Overall diameter30.96"30.98"+0.02" (+0.06%)
Section width325 mm285 mm-40 mm
Sidewall4.48"4.49"+0.01"
Rim22"22"same
Circumference97.3"97.3"+0.1"
Revs per mile651651-0
Ride height——+0.01"
Speedometer reads 60 mph60.060.0+0.0 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.0 mph

With 285/40R22 on a car calibrated for 325/35R22, the speedometer reads 60.0 mph when you're really doing 60, and the odometer under-counts by 0.1%.

Speedo showsActual speed
30 mph30.0 mph
45 mph45.0 mph
60 mph60.0 mph
70 mph70.0 mph
80 mph80.1 mph

Other sizes close to 325/35R22

Questions

Can I replace 325/35R22 with 285/40R22?

285/40R22 is a safe swap for 325/35R22 by the usual ±3% rule: the diameter differs by +0.06%.

What's the difference between 325/35R22 and 285/40R22?

285/40R22 is 0.02" taller and 40 mm narrower; the sidewall is +0.01". At an indicated 60 mph you'd actually be doing 60.0 mph.

Will 285/40R22 fit on 325/35R22 wheels?

Both use a 22" rim, so the wheel diameter matches; check the wheel's width range for a 285 mm tire and the fender clearance.