215/60R17 vs 255/45R18 tire size
255/45R18 vs 215/60R17, diameter
-0.4% shorter
- Speedometer
- 60.3 mph
- At a true 60 mph
- Diameter
- 27.04 in
- Was 27.16 in
- Revs per mile
- 746
- Was 743
- 3% guideline
- Within
Car built for 215/60R17, now on 255/45R18.
215/60R17 and 255/45R18
| Measure | 215/60R17 | 255/45R18 | Difference |
|---|---|---|---|
| Width, mm | 215 | 255 | +40 |
| Sidewall, % of width | 60 | 45 | -15 |
| Rim, in | 17 | 18 | +1 |
| Section height, in | 5.08 | 4.52 | -0.56 |
| Diameter, in | 27.16 | 27.04 | -0.12 (-0.4%) |
| Circumference, in | 85.3 | 84.9 | -0.4 |
| Revs per mile | 743 | 746 | +3 (+0.5%) |
Fitting 255/45R18 instead of 215/60R17
Within the usual 3% diameter guideline.
- Needs 18 in wheels.
- 40 mm wider. Check rubbing at full lock.
- Shorter sidewall: 0.6 in less.
Cars with 215/60R17
Cars with 255/45R18
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