235/55R19 vs 255/45R20

255/45R20 is 3.0 mm shorter than 235/55R19 in overall diameter (−0.4%), 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 99.6 km/h.

Dimensions side by side

	235/55R19	255/45R20
Overall diameter	741 mm (29.2″)	738 mm (29.1″)
Section width	235 mm	255 mm
Sidewall height	129 mm	115 mm
Rim	19″	20″
Revolutions per km	430	431
In stock	126 tires from $178.00	81 tires from $173.00

What changes

Overall diameter: 255/45R20 is 3.0 mm shorter (−0.4%).
Speedometer: reads 100 km/h at an actual 99.6 km/h with 255/45R20.
255/45R20 is 20 mm wider, so check clearance and the recommended rim width.
Wheel size changes from 19″ 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 235/55R19

Vehicles that use 255/45R20

See every alternate size for 235/55R19

Frequently asked questions

Can I use 255/45R20 instead of 235/55R19?

Usually, yes: 255/45R20 is within 3% of the overall diameter of 235/55R19 (−0.4%). 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 235/55R19 and 255/45R20?

With 255/45R20 instead of 235/55R19, the speedometer shows 100 km/h when you are actually doing 99.6 km/h.

Which vehicles came with both 235/55R19 and 255/45R20?

Both sizes were original equipment, on different trims or packages, on the 2009–2024 Audi Q5, 2010–2014, 2018–2024 Volvo XC60, 2018–2024 Alfa Romeo Stelvio, 2016–2024 Mercedes-Benz GLC300, 2019–2020, 2023–2024 Infiniti QX50, 2017–2024 Mercedes-Benz GLC 300.