235/45R20 vs 305/35R20 tire size
305/35R20 vs 235/45R20, diameter
+0.3% taller
- Speedometer
- 59.8 mph
- At a true 60 mph
- Diameter
- 28.41 in
- Was 28.33 in
- Revs per mile
- 710
- Was 712
- 3% guideline
- Within
Car built for 235/45R20, now on 305/35R20.
235/45R20 and 305/35R20
| Measure | 235/45R20 | 305/35R20 | Difference |
|---|---|---|---|
| Width, mm | 235 | 305 | +70 |
| Sidewall, % of width | 45 | 35 | -10 |
| Rim, in | 20 | 20 | 0 |
| Section height, in | 4.16 | 4.20 | +0.04 |
| Diameter, in | 28.33 | 28.41 | +0.08 (+0.3%) |
| Circumference, in | 89.0 | 89.2 | +0.2 |
| Revs per mile | 712 | 710 | -2 (-0.3%) |
Fitting 305/35R20 instead of 235/45R20
Within the usual 3% diameter guideline.
- 70 mm wider. Check rubbing at full lock.
Cars with 235/45R20
Cars with 305/35R20
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