245/45R20 vs 305/35R20 tire size
305/35R20 vs 245/45R20, diameter
-1.0% shorter
- Speedometer
- 60.6 mph
- At a true 60 mph
- Diameter
- 28.41 in
- Was 28.68 in
- Revs per mile
- 710
- Was 703
- 3% guideline
- Within
Car built for 245/45R20, now on 305/35R20.
245/45R20 and 305/35R20
| Measure | 245/45R20 | 305/35R20 | Difference |
|---|---|---|---|
| Width, mm | 245 | 305 | +60 |
| Sidewall, % of width | 45 | 35 | -10 |
| Rim, in | 20 | 20 | 0 |
| Section height, in | 4.34 | 4.20 | -0.14 |
| Diameter, in | 28.68 | 28.41 | -0.28 (-1.0%) |
| Circumference, in | 90.1 | 89.2 | -0.9 |
| Revs per mile | 703 | 710 | +7 (+1.0%) |
Fitting 305/35R20 instead of 245/45R20
Within the usual 3% diameter guideline.
- 60 mm wider. Check rubbing at full lock.
Cars with 245/45R20
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