245/40R18 vs 285/30R19 tire size
285/30R19 vs 245/40R18, diameter
Same diameter
- Speedometer
- 60.0 mph
- At a true 60 mph
- Diameter
- 25.73 in
- Was 25.72 in
- Revs per mile
- 784
- Was 784
- 3% guideline
- Within
Car built for 245/40R18, now on 285/30R19.
245/40R18 and 285/30R19
| Measure | 245/40R18 | 285/30R19 | Difference |
|---|---|---|---|
| Width, mm | 245 | 285 | +40 |
| Sidewall, % of width | 40 | 30 | -10 |
| Rim, in | 18 | 19 | +1 |
| Section height, in | 3.86 | 3.37 | -0.49 |
| Diameter, in | 25.72 | 25.73 | +0.02 (+0.1%) |
| Circumference, in | 80.8 | 80.8 | +0.0 |
| Revs per mile | 784 | 784 | -0 (-0.1%) |
Fitting 285/30R19 instead of 245/40R18
Within the usual 3% diameter guideline.
- Needs 19 in wheels.
- 40 mm wider. Check rubbing at full lock.
Cars with 245/40R18
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