245/35R21 vs 275/30R21 tire size
275/30R21 vs 245/35R21, diameter
-0.9% shorter
- Speedometer
- 60.6 mph
- At a true 60 mph
- Diameter
- 27.50 in
- Was 27.75 in
- Revs per mile
- 733
- Was 727
- 3% guideline
- Within
Car built for 245/35R21, now on 275/30R21.
245/35R21 and 275/30R21
| Measure | 245/35R21 | 275/30R21 | Difference |
|---|---|---|---|
| Width, mm | 245 | 275 | +30 |
| Sidewall, % of width | 35 | 30 | -5 |
| Rim, in | 21 | 21 | 0 |
| Section height, in | 3.38 | 3.25 | -0.13 |
| Diameter, in | 27.75 | 27.50 | -0.26 (-0.9%) |
| Circumference, in | 87.2 | 86.4 | -0.8 |
| Revs per mile | 727 | 733 | +7 (+0.9%) |
Fitting 275/30R21 instead of 245/35R21
Within the usual 3% diameter guideline.
- 30 mm wider. Check rubbing at full lock.
Cars with 245/35R21
Cars with 275/30R21
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