225/65R17 vs 255/50R18 tire size
255/50R18 vs 225/65R17, diameter
-1.7% shorter
- Speedometer
- 61.0 mph
- At a true 60 mph
- Diameter
- 28.04 in
- Was 28.52 in
- Revs per mile
- 719
- Was 707
- 3% guideline
- Within
Car built for 225/65R17, now on 255/50R18.
225/65R17 and 255/50R18
| Measure | 225/65R17 | 255/50R18 | Difference |
|---|---|---|---|
| Width, mm | 225 | 255 | +30 |
| Sidewall, % of width | 65 | 50 | -15 |
| Rim, in | 17 | 18 | +1 |
| Section height, in | 5.76 | 5.02 | -0.74 |
| Diameter, in | 28.52 | 28.04 | -0.48 (-1.7%) |
| Circumference, in | 89.6 | 88.1 | -1.5 |
| Revs per mile | 707 | 719 | +12 (+1.7%) |
Fitting 255/50R18 instead of 225/65R17
Within the usual 3% diameter guideline.
- Needs 18 in wheels.
- 30 mm wider. Check rubbing at full lock.
- Shorter sidewall: 0.7 in less.
Cars with 225/65R17
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