CarSpecsHQ

315/30R22 vs 265/40R22

265/40R22 is outside the ±3% rule as a replacement for 315/30R22: the diameter differs by +3.08%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

22" rim
315/30R22 29.44" · 265/40R22 30.35" · drawn to scale

Side by side

315/30R22265/40R22Difference
Overall diameter29.44"30.35"+0.91" (+3.08%)
Section width315 mm265 mm-50 mm
Sidewall3.72"4.17"+0.45"
Rim22"22"same
Circumference92.5"95.3"+2.8"
Revs per mile685665-20
Ride height——+0.45"
Speedometer reads 60 mph60.061.8+1.8 mph

Speedometer and odometer

020406080100120 reads 60 · actual 61.8 mph

With 265/40R22 on a car calibrated for 315/30R22, the speedometer reads 58.2 mph when you're really doing 60, and the odometer under-counts by 3.1%.

Speedo showsActual speed
30 mph30.9 mph
45 mph46.4 mph
60 mph61.8 mph
70 mph72.2 mph
80 mph82.5 mph

Other sizes close to 315/30R22

Questions

Can I replace 315/30R22 with 265/40R22?

265/40R22 is outside the ±3% rule as a replacement for 315/30R22: the diameter differs by +3.08%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 315/30R22 and 265/40R22?

265/40R22 is 0.91" taller and 50 mm narrower; the sidewall is +0.45". At an indicated 60 mph you'd actually be doing 61.8 mph.

Will 265/40R22 fit on 315/30R22 wheels?

Both use a 22" rim, so the wheel diameter matches; check the wheel's width range for a 265 mm tire and the fender clearance.