CarSpecsHQ

295/40R18 vs 215/55R18

215/55R18 is a safe swap for 295/40R18 by the usual ±3% rule: the diameter differs by +0.07%.

18" rim
295/40R18 27.29" · 215/55R18 27.31" · drawn to scale

Side by side

295/40R18215/55R18Difference
Overall diameter27.29"27.31"+0.02" (+0.07%)
Section width295 mm215 mm-80 mm
Sidewall4.65"4.66"+0.01"
Rim18"18"same
Circumference85.7"85.8"+0.1"
Revs per mile739738-1
Ride height——+0.01"
Speedometer reads 60 mph60.060.0+0.0 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.0 mph

With 215/55R18 on a car calibrated for 295/40R18, 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 mph70.1 mph
80 mph80.1 mph

Other sizes close to 295/40R18

Questions

Can I replace 295/40R18 with 215/55R18?

215/55R18 is a safe swap for 295/40R18 by the usual ±3% rule: the diameter differs by +0.07%.

What's the difference between 295/40R18 and 215/55R18?

215/55R18 is 0.02" taller and 80 mm narrower; the sidewall is +0.01". At an indicated 60 mph you'd actually be doing 60.0 mph.

Will 215/55R18 fit on 295/40R18 wheels?

Both use a 18" rim, so the wheel diameter matches; check the wheel's width range for a 215 mm tire and the fender clearance.