CarSpecsHQ

265/40R18 vs 295/40R18

295/40R18 is outside the ±3% rule as a replacement for 265/40R18: the diameter differs by +3.59%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

18" rim
265/40R18 26.35" · 295/40R18 27.29" · drawn to scale

Side by side

265/40R18295/40R18Difference
Overall diameter26.35"27.29"+0.94" (+3.59%)
Section width265 mm295 mm+30 mm
Sidewall4.17"4.65"+0.47"
Rim18"18"same
Circumference82.8"85.7"+3.0"
Revs per mile765739-27
Ride height——+0.47"
Speedometer reads 60 mph60.062.2+2.2 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.2 mph

With 295/40R18 on a car calibrated for 265/40R18, 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 265/40R18

Questions

Can I replace 265/40R18 with 295/40R18?

295/40R18 is outside the ±3% rule as a replacement for 265/40R18: the diameter differs by +3.59%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 265/40R18 and 295/40R18?

295/40R18 is 0.94" taller and 30 mm wider; the sidewall is +0.47". At an indicated 60 mph you'd actually be doing 62.2 mph.

Will 295/40R18 fit on 265/40R18 wheels?

Both use a 18" rim, so the wheel diameter matches; check the wheel's width range for a 295 mm tire and the fender clearance.