Skip to content
GizmoDriver

225/45R17 vs 245/35R18 tire size

245/35R18 vs 225/45R17, diameter

-0.9% shorter

Speedometer
60.5 mph
At a true 60 mph
Diameter
24.75 in
Was 24.97 in
Revs per mile
815
Was 808
3% guideline
Within

Car built for 225/45R17, now on 245/35R18.

225/45R17 and 245/35R18

225/45R17 vs 245/35R18 tire size
Measure225/45R17245/35R18Difference
Width, mm225245+20
Sidewall, % of width4535-10
Rim, in1718+1
Section height, in3.993.38-0.61
Diameter, in24.9724.75-0.22 (-0.9%)
Circumference, in78.577.8-0.7
Revs per mile808815+7 (+0.9%)

Fitting 245/35R18 instead of 225/45R17

Within the usual 3% diameter guideline.

  • Needs 18 in wheels.
  • 20 mm wider. Check rubbing at full lock.
  • Shorter sidewall: 0.6 in less.

Cars with 225/45R17

What this cannot tell you

Diameter within 3% is a common shop guideline, not a maker spec.

Load index, offset and clearance are not in this data.

How values are checked