215/55R16 vs 235/40R18
235/40R18 is 2.0 mm taller than 215/55R16 in overall diameter (+0.3%), within the usual 3% limit, so it can replace it where the wheels and clearance allow. With 235/40R18 fitted, the speedometer reads 100 km/h when you are doing 100.3 km/h.
Dimensions side by side
| 215/55R16 | 235/40R18 | |
|---|---|---|
| Overall diameter | 643 mm (25.3″) | 645 mm (25.4″) |
| Section width | 215 mm | 235 mm |
| Sidewall height | 118 mm | 94 mm |
| Rim | 16″ | 18″ |
| Revolutions per km | 495 | 494 |
| In stock | 45 tires from $103.00 | 45 tires from $110.00 |
What changes
- Overall diameter: 235/40R18 is 2.0 mm taller (+0.3%).
- Speedometer: reads 100 km/h at an actual 100.3 km/h with 235/40R18.
- 235/40R18 is 20 mm wider, so check clearance and the recommended rim width.
- Wheel size changes from 16″ 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 215/55R16
Vehicles that use 235/40R18
See every alternate size for 215/55R16
Frequently asked questions
Can I use 235/40R18 instead of 215/55R16?
Usually, yes: 235/40R18 is within 3% of the overall diameter of 215/55R16 (+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 215/55R16 and 235/40R18?
With 235/40R18 instead of 215/55R16, the speedometer shows 100 km/h when you are actually doing 100.3 km/h.
Which vehicles came with both 215/55R16 and 235/40R18?
Both sizes were original equipment, on different trims or packages, on the 2007–2010 Volkswagen Eos, 2007 Volkswagen Passat, 2004–2005 Volvo S60.