235/55R17 vs 235/50R18 tire size
235/50R18 vs 235/55R17, diameter
+0.3% taller
- Speedometer
- 59.8 mph
- At a true 60 mph
- Diameter
- 27.25 in
- Was 27.18 in
- Revs per mile
- 740
- Was 742
- 3% guideline
- Within
Car built for 235/55R17, now on 235/50R18.
235/55R17 and 235/50R18
| Measure | 235/55R17 | 235/50R18 | Difference |
|---|---|---|---|
| Width, mm | 235 | 235 | 0 |
| Sidewall, % of width | 55 | 50 | -5 |
| Rim, in | 17 | 18 | +1 |
| Section height, in | 5.09 | 4.63 | -0.46 |
| Diameter, in | 27.18 | 27.25 | +0.07 (+0.3%) |
| Circumference, in | 85.4 | 85.6 | +0.2 |
| Revs per mile | 742 | 740 | -2 (-0.3%) |
Fitting 235/50R18 instead of 235/55R17
Within the usual 3% diameter guideline.
- Needs 18 in wheels.
Cars with 235/50R18
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.
- Two or more sources agree
- One source
- Model-level or estimate
- Sources differ