255/45R20 vs 325/35R20 tire size
325/35R20 vs 255/45R20, diameter
-0.3% shorter
- Speedometer
- 60.2 mph
- At a true 60 mph
- Diameter
- 28.96 in
- Was 29.04 in
- Revs per mile
- 696
- Was 695
- 3% guideline
- Within
Car built for 255/45R20, now on 325/35R20.
255/45R20 and 325/35R20
| Measure | 255/45R20 | 325/35R20 | Difference |
|---|---|---|---|
| Width, mm | 255 | 325 | +70 |
| Sidewall, % of width | 45 | 35 | -10 |
| Rim, in | 20 | 20 | 0 |
| Section height, in | 4.52 | 4.48 | -0.04 |
| Diameter, in | 29.04 | 28.96 | -0.08 (-0.3%) |
| Circumference, in | 91.2 | 91.0 | -0.2 |
| Revs per mile | 695 | 696 | +2 (+0.3%) |
Fitting 325/35R20 instead of 255/45R20
Within the usual 3% diameter guideline.
- 70 mm wider. Check rubbing at full lock.
Cars with 255/45R20
Cars with 325/35R20
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