225/60R18 vs 245/45R20
245/45R20 is 2.0 mm taller than 225/60R18 in overall diameter (+0.3%), within the usual 3% limit, so it can replace it where the wheels and clearance allow. With 245/45R20 fitted, the speedometer reads 100 km/h when you are doing 100.3 km/h.
Dimensions side by side
| 225/60R18 | 245/45R20 | |
|---|---|---|
| Overall diameter | 727 mm (28.6″) | 729 mm (28.7″) |
| Section width | 225 mm | 245 mm |
| Sidewall height | 135 mm | 110 mm |
| Rim | 18″ | 20″ |
| Revolutions per km | 438 | 437 |
| In stock | 75 tires from $123.00 | 52 tires from $167.00 |
What changes
- Overall diameter: 245/45R20 is 2.0 mm taller (+0.3%).
- Speedometer: reads 100 km/h at an actual 100.3 km/h with 245/45R20.
- 245/45R20 is 20 mm wider, so check clearance and the recommended rim width.
- Wheel size changes from 18″ to 20″: you need wheels in the new size.
- Choose a load index at least as high as the one on your door placard.
Vehicles that came with both sizes
Vehicles that use 225/60R18
Vehicles that use 245/45R20
See every alternate size for 225/60R18
Frequently asked questions
Can I use 245/45R20 instead of 225/60R18?
Usually, yes: 245/45R20 is within 3% of the overall diameter of 225/60R18 (+0.3%). Use wheels of the right size and width, match or exceed the original load index, and check clearance at full steering lock.
How much does the speedometer change between 225/60R18 and 245/45R20?
With 245/45R20 instead of 225/60R18, the speedometer shows 100 km/h when you are actually doing 100.3 km/h.
Which vehicles came with both 225/60R18 and 245/45R20?
Both sizes were original equipment, on different trims or packages, on the 2022–2024 Lincoln Corsair, 2011–2012, 2018–2022 Chrysler 300, 2007–2017 Chrysler 300C, 2007–2010 Dodge Charger, 2007–2008 Dodge Magnum.