CarSpecsHQ

285/40R23 vs 285/45R22

285/45R22 is a safe swap for 285/40R23 by the usual ±3% rule: the diameter differs by +0.38%.

23" → 22"
285/40R23 31.98" · 285/45R22 32.10" · drawn to scale

Side by side

285/40R23285/45R22Difference
Overall diameter31.98"32.10"+0.12" (+0.38%)
Section width285 mm285 mm0 mm
Sidewall4.49"5.05"+0.56"
Rim23"22"-1"
Circumference100.5"100.8"+0.4"
Revs per mile631628-2
Ride height——+0.06"
Speedometer reads 60 mph60.060.2+0.2 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.2 mph

With 285/45R22 on a car calibrated for 285/40R23, the speedometer reads 59.8 mph when you're really doing 60, and the odometer under-counts by 0.4%.

Speedo showsActual speed
30 mph30.1 mph
45 mph45.2 mph
60 mph60.2 mph
70 mph70.3 mph
80 mph80.3 mph

Other sizes close to 285/40R23

Questions

Can I replace 285/40R23 with 285/45R22?

285/45R22 is a safe swap for 285/40R23 by the usual ±3% rule: the diameter differs by +0.38%.

What's the difference between 285/40R23 and 285/45R22?

285/45R22 is 0.12" taller and 0 mm wider; the sidewall is +0.56". At an indicated 60 mph you'd actually be doing 60.2 mph.

Will 285/45R22 fit on 285/40R23 wheels?

No — 285/40R23 needs a 23" wheel and 285/45R22 a 22" wheel. This is a plus/minus-size swap that changes wheels too.