Skip to content
GizmoDriver

255/60R17 vs 255/55R18 tire size

255/55R18 vs 255/60R17, diameter

Same diameter

Speedometer
60.0 mph
At a true 60 mph
Diameter
29.04 in
Was 29.05 in
Revs per mile
694
Was 694
3% guideline
Within

Car built for 255/60R17, now on 255/55R18.

255/60R17 and 255/55R18

255/60R17 vs 255/55R18 tire size
Measure255/60R17255/55R18Difference
Width, mm2552550
Sidewall, % of width6055-5
Rim, in1718+1
Section height, in6.025.52-0.50
Diameter, in29.0529.040 (-0.0%)
Circumference, in91.391.2-0.0
Revs per mile694694+0 (+0.0%)

Fitting 255/55R18 instead of 255/60R17

Within the usual 3% diameter guideline.

  • Needs 18 in wheels.
  • Shorter sidewall: 0.5 in less.

Cars with 255/60R17

Cars with 255/55R18

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