CarSpecsHQ

215/45R17 vs 275/40R17

275/40R17 is outside the ±3% rule as a replacement for 215/45R17: the diameter differs by +4.24%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

17" rim
215/45R17 24.62" · 275/40R17 25.66" · drawn to scale

Side by side

215/45R17275/40R17Difference
Overall diameter24.62"25.66"+1.04" (+4.24%)
Section width215 mm275 mm+60 mm
Sidewall3.81"4.33"+0.52"
Rim17"17"same
Circumference77.3"80.6"+3.3"
Revs per mile819786-33
Ride height——+0.52"
Speedometer reads 60 mph60.062.5+2.5 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.5 mph

With 275/40R17 on a car calibrated for 215/45R17, the speedometer reads 57.6 mph when you're really doing 60, and the odometer under-counts by 4.2%.

Speedo showsActual speed
30 mph31.3 mph
45 mph46.9 mph
60 mph62.5 mph
70 mph73.0 mph
80 mph83.4 mph

Other sizes close to 215/45R17

Questions

Can I replace 215/45R17 with 275/40R17?

275/40R17 is outside the ±3% rule as a replacement for 215/45R17: the diameter differs by +4.24%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 215/45R17 and 275/40R17?

275/40R17 is 1.04" taller and 60 mm wider; the sidewall is +0.52". At an indicated 60 mph you'd actually be doing 62.5 mph.

Will 275/40R17 fit on 215/45R17 wheels?

Both use a 17" rim, so the wheel diameter matches; check the wheel's width range for a 275 mm tire and the fender clearance.