255/50R19 vs 255/55R18
255/55R18 is 0.0 mm taller than 255/50R19 in overall diameter (±0.0%), within the usual 3% limit, so it can replace it where the wheels and clearance allow. With 255/55R18 fitted, the speedometer reads 100 km/h when you are doing 100.0 km/h.
Dimensions side by side
| 255/50R19 | 255/55R18 | |
|---|---|---|
| Overall diameter | 738 mm (29.1″) | 738 mm (29.1″) |
| Section width | 255 mm | 255 mm |
| Sidewall height | 128 mm | 140 mm |
| Rim | 19″ | 18″ |
| Revolutions per km | 431 | 431 |
| In stock | 56 tires from $160.00 | 27 tires from $160.00 |
What changes
- Overall diameter: 255/55R18 is 0.0 mm taller (±0.0%).
- Speedometer: reads 100 km/h at an actual 100.0 km/h with 255/55R18.
- Wheel size changes from 19″ to 18″: 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 255/50R19
Vehicles that use 255/55R18
See every alternate size for 255/50R19
Frequently asked questions
Can I use 255/55R18 instead of 255/50R19?
Usually, yes: 255/55R18 is within 3% of the overall diameter of 255/50R19 (±0.0%). 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 255/50R19 and 255/55R18?
With 255/55R18 instead of 255/50R19, the speedometer shows 100 km/h when you are actually doing 100.0 km/h.
Which vehicles came with both 255/50R19 and 255/55R18?
Both sizes were original equipment, on different trims or packages, on the 2015–2021 Porsche Macan, 2016 Mercedes-Benz GLE300d, 2015 Mercedes-Benz ML250, 2003–2013 BMW X5, 2006–2011 Mercedes-Benz R350, 2007–2008 Mercedes-Benz R320.