305/35R21 vs 315/30R22
315/30R22 is 1.0 mm taller than 305/35R21 in overall diameter (+0.1%), within the usual 3% limit, so it can replace it where the wheels and clearance allow. With 315/30R22 fitted, the speedometer reads 100 km/h when you are doing 100.1 km/h.
Dimensions side by side
| 305/35R21 | 315/30R22 | |
|---|---|---|
| Overall diameter | 747 mm (29.4″) | 748 mm (29.4″) |
| Section width | 305 mm | 315 mm |
| Sidewall height | 107 mm | 95 mm |
| Rim | 21″ | 22″ |
| Revolutions per km | 426 | 426 |
| In stock | 3 tires from $552.00 | 9 tires from $480.00 |
What changes
- Overall diameter: 315/30R22 is 1.0 mm taller (+0.1%).
- Speedometer: reads 100 km/h at an actual 100.1 km/h with 315/30R22.
- 315/30R22 is 10 mm wider, so check clearance and the recommended rim width.
- Wheel size changes from 21″ to 22″: 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 305/35R21
Vehicles that use 315/30R22
See every alternate size for 305/35R21
Frequently asked questions
Can I use 315/30R22 instead of 305/35R21?
Usually, yes: 315/30R22 is within 3% of the overall diameter of 305/35R21 (+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 305/35R21 and 315/30R22?
With 315/30R22 instead of 305/35R21, the speedometer shows 100 km/h when you are actually doing 100.1 km/h.
Which vehicles came with both 305/35R21 and 315/30R22?
Both sizes were original equipment, on different trims or packages, on the 2020–2024 Bentley Flying Spur, 2024 Bentley Continental GT, 2019–2023 Bentley Continental.