245/35R21 vs 285/30R21
285/30R21 is 1.0 mm shorter than 245/35R21 in overall diameter (−0.1%), within the usual 3% limit, so it can replace it where the wheels and clearance allow. With 285/30R21 fitted, the speedometer reads 100 km/h when you are doing 99.9 km/h.
Dimensions side by side
| 245/35R21 | 285/30R21 | |
|---|---|---|
| Overall diameter | 705 mm (27.8″) | 704 mm (27.7″) |
| Section width | 245 mm | 285 mm |
| Sidewall height | 86 mm | 86 mm |
| Rim | 21″ | 21″ |
| Revolutions per km | 452 | 452 |
| In stock | 10 tires from $339.00 | 2 tires from $606.00 |
What changes
- Overall diameter: 285/30R21 is 1.0 mm shorter (−0.1%).
- Speedometer: reads 100 km/h at an actual 99.9 km/h with 285/30R21.
- 285/30R21 is 40 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 245/35R21
Vehicles that use 285/30R21
See every alternate size for 245/35R21
Frequently asked questions
Can I use 285/30R21 instead of 245/35R21?
Usually, yes: 285/30R21 is within 3% of the overall diameter of 245/35R21 (−0.1%). 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 245/35R21 and 285/30R21?
With 285/30R21 instead of 245/35R21, the speedometer shows 100 km/h when you are actually doing 99.9 km/h.
Which vehicles came with both 245/35R21 and 285/30R21?
Both sizes were original equipment, on different trims or packages, on the 2014–2024 Maserati Ghibli, 2014–2024 Maserati Quattroporte, 2007–2008, 2011–2013, 2016–2024 BMW Alpina, 2006–2008 BMW 750i, 2006–2008 BMW 750Li, 2006–2008 BMW 760i.