285/35R22 vs 285/40R21
285/40R21 is 3.0 mm taller than 285/35R22 in overall diameter (+0.4%), within the usual 3% limit, so it can replace it where the wheels and clearance allow. With 285/40R21 fitted, the speedometer reads 100 km/h when you are doing 100.4 km/h.
Dimensions side by side
| 285/35R22 | 285/40R21 | |
|---|---|---|
| Overall diameter | 758 mm (29.8″) | 761 mm (30.0″) |
| Section width | 285 mm | 285 mm |
| Sidewall height | 100 mm | 114 mm |
| Rim | 22″ | 21″ |
| Revolutions per km | 420 | 418 |
| In stock | 11 tires from $181.00 | 11 tires from $316.00 |
What changes
- Overall diameter: 285/40R21 is 3.0 mm taller (+0.4%).
- Speedometer: reads 100 km/h at an actual 100.4 km/h with 285/40R21.
- Wheel size changes from 22″ to 21″: 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 285/35R22
Vehicles that use 285/40R21
See every alternate size for 285/35R22
Frequently asked questions
Can I use 285/40R21 instead of 285/35R22?
Usually, yes: 285/40R21 is within 3% of the overall diameter of 285/35R22 (+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 285/35R22 and 285/40R21?
With 285/40R21 instead of 285/35R22, the speedometer shows 100 km/h when you are actually doing 100.4 km/h.
Which vehicles came with both 285/35R22 and 285/40R21?
Both sizes were original equipment, on different trims or packages, on the 2024 Audi SQ7, 2019–2023 Porsche Cayenne, 2019–2023 Audi Q7.