235/70R17 vs 245/60R18 tire size
245/60R18 vs 235/70R17, diameter
-1.3% shorter
- Speedometer
- 60.8 mph
- At a true 60 mph
- Diameter
- 29.57 in
- Was 29.95 in
- Revs per mile
- 682
- Was 673
- 3% guideline
- Within
Car built for 235/70R17, now on 245/60R18.
235/70R17 and 245/60R18
| Measure | 235/70R17 | 245/60R18 | Difference |
|---|---|---|---|
| Width, mm | 235 | 245 | +10 |
| Sidewall, % of width | 70 | 60 | -10 |
| Rim, in | 17 | 18 | +1 |
| Section height, in | 6.48 | 5.79 | -0.69 |
| Diameter, in | 29.95 | 29.57 | -0.38 (-1.3%) |
| Circumference, in | 94.1 | 92.9 | -1.2 |
| Revs per mile | 673 | 682 | +9 (+1.3%) |
Fitting 245/60R18 instead of 235/70R17
Within the usual 3% diameter guideline.
- Needs 18 in wheels.
- Shorter sidewall: 0.7 in less.
Cars with 245/60R18
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