245/45R20 vs 255/45R20
255/45R20 is 9.0 mm taller than 245/45R20 in overall diameter (+1.2%), within the usual 3% limit, so it can replace it where the wheels and clearance allow. With 255/45R20 fitted, the speedometer reads 100 km/h when you are doing 101.2 km/h.
Dimensions side by side
| 245/45R20 | 255/45R20 | |
|---|---|---|
| Overall diameter | 729 mm (28.7″) | 738 mm (29.1″) |
| Section width | 245 mm | 255 mm |
| Sidewall height | 110 mm | 115 mm |
| Rim | 20″ | 20″ |
| Revolutions per km | 437 | 431 |
| In stock | 52 tires from $167.00 | 81 tires from $173.00 |
What changes
- Overall diameter: 255/45R20 is 9.0 mm taller (+1.2%).
- Speedometer: reads 100 km/h at an actual 101.2 km/h with 255/45R20.
- 255/45R20 is 10 mm wider, so check clearance and the recommended rim width.
- Choose a load index at least as high as the one on your door placard.
Vehicles that came with both sizes
Vehicles that use 245/45R20
Vehicles that use 255/45R20
See every alternate size for 245/45R20
Frequently asked questions
Can I use 255/45R20 instead of 245/45R20?
Usually, yes: 255/45R20 is within 3% of the overall diameter of 245/45R20 (+1.2%). 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 245/45R20 and 255/45R20?
With 255/45R20 instead of 245/45R20, the speedometer shows 100 km/h when you are actually doing 101.2 km/h.
Which vehicles came with both 245/45R20 and 255/45R20?
Both sizes were original equipment, on different trims or packages, on the 2008–2014 Dodge Challenger, 2005–2010 Chrysler 300C, 2006–2010 Dodge Charger, 2006–2008 Dodge Magnum.