Alpina · XD4 · kPa
Alpina XD4 kPa inflation table
- Drivetrain
- rear-wheel drive
- Body
- passenger car
- PSI F / R
- 32-35 / 32-35
- Bar F / R
- 2.2-2.4 / 2.2-2.4
kPa
231 / 231
2.31 / 2.31 bar · 32-35 / 32-35 psi
32-35 psi F · 32-35 psi R · 2.2-2.4 / 2.2-2.4 bar · 231/231 kPa
Kilopascals show up on some Asian stickers and ISO sheets. 231 kPa front and 231 kPa rear is the Alpina XD4 midpoint (100 kPa = 1 bar). TPMS typically warns near 25 psi (about 25% below target). That is already a soft tyre, not a fill target.
kPa, bar and PSI
kPa-led conversions. 220 kPa is 2.2 bar and about 32 psi — handy if this XD4 sticker uses SI units.
| kPa | Bar | PSI |
|---|---|---|
| 207 | 2.07 | 30 |
| 221 | 2.21 | 32 |
| 228 | 2.28 | 33 |
| 231 | 2.31 | 33.5 |
| 241 | 2.41 | 35 |
| 248 | 2.48 | 36 |
| 262 | 2.62 | 38 |
| 276 | 2.76 | 40 |
| 303 | 3.03 | 44 |
| 345 | 3.45 | 50 |
| 414 | 4.14 | 60 |
Estimated pressure by tyre size (225/50R17 and others)
Planning cold pressures for sizes often seen on a passenger car. This XD4 sample opens with 225/50R17, then 185/65R15 and 195/65R15.
| Tyre size | Front PSI | Rear PSI | Front bar | Rear bar | Front kPa | Rear kPa | Note |
|---|---|---|---|---|---|---|---|
| 225/50R17 | 35 | 35 | 2.41 | 2.41 | 241 | 241 | Touring 17-inch |
| 185/65R15 | 33 | 33 | 2.28 | 2.28 | 228 | 228 | Small / older car |
| 195/65R15 | 34 | 34 | 2.34 | 2.34 | 234 | 234 | Very common compact |
| 245/40R18 | 36 | 36 | 2.48 | 2.48 | 248 | 248 | Wide touring 18-inch |
| 225/45R17 | 35 | 35 | 2.41 | 2.41 | 241 | 241 | Sport 17-inch |
| 205/60R16 | 34 | 34 | 2.34 | 2.34 | 234 | 234 | Taller 16-inch |
| 215/55R16 | 34 | 35 | 2.34 | 2.41 | 234 | 241 | Slightly wider 16-inch |
| 205/55R16 | 34 | 34 | 2.34 | 2.34 | 234 | 234 | Typical mid-compact OEM |
Alpina XD4 placard versus sidewall
The tyre-information placard on a Alpina XD4 sits on the driver’s door pillar (sometimes the fuel-filler flap). Catalogue figures here are a general band: 32-35 / 32-35 psi.
Temperature drift
Roughly 1 psi per 5–6 °C. The table uses 34 psi as a 20 °C baseline for this XD4.
| Ambient | Gauge (front mid) | Bar | kPa | Note |
|---|---|---|---|---|
| −5 °C (hard frost) | 31 psi | 2.14 bar | 214 kPa | Gauge reads low; do not overfill once warm |
| 0 °C | 32 psi | 2.21 bar | 221 kPa | Gauge reads low; do not overfill once warm |
| 8 °C (UK winter morning) | 33 psi | 2.28 bar | 228 kPa | Gauge reads low; do not overfill once warm |
| 20 °C (set cold here) | 34 psi | 2.34 bar | 234 kPa | Baseline |
| 30 °C | 36 psi | 2.48 bar | 248 kPa | Do not bleed a hot tyre |
| 38 °C (heatwave tarmac) | 37 psi | 2.55 bar | 255 kPa | Do not bleed a hot tyre |
How to set the XD4
- Measure before the school run, not after the M25.
- Write LF / RF / RR / RL. Do not keep XD4 numbers in your head.
- Add air in short bursts toward 34 psi (2.31 bar) front and 34 psi rear.
- If one corner is 4 psi down, hunt for a nail before you blame the weather.
- Log date, ambient temperature and the four readings.
Load notes
Load moves the rear of a passenger car first. If the factory placard already has a “laden” column, use that instead of these sketches.
| Condition | Front (est.) | Rear (est.) |
|---|---|---|
| Driver only | 34 psi / 2.34 bar | 34 psi / 2.34 bar |
| Full occupancy | 34 psi / 2.34 bar | 35 psi / 2.41 bar |
| Motorway + luggage | 35 psi / 2.41 bar | 38 psi / 2.62 bar |
Alpina notes
No special Alpina exception: the XD4 uses the door-pillar placard. Size estimates on this page only help if you have left the original load index behind.
Spare and inflator kit
A matching full-size spare on the Alpina XD4 usually follows the higher axle (often the rear, near 32-35 psi). A space-saver is commonly 60 psi / 4.1 bar — read that tyre’s own sidewall. An inflator kit is not a spare; check the sealant date.
If the Alpina sticker and this page disagree, the sticker wins.
Other Alpina models
Questions about this XD4
Front versus rear on the Alpina XD4?
This row is 32-35 F / 32-35 R. Even when they match, a laden rear can justify a higher number if the sticker prints one.
What tyre pressure should a Alpina XD4 use?
Catalogue reference is 32-35 psi front and 32-35 psi rear (2.2-2.4 / 2.2-2.4 bar), cold. Confirm on the door-pillar placard.
What PSI if I plus-size toward 195/65R15?
Keep load index at or above OEM. Low-profile sizes usually stay at or slightly above the placard. Use 225/50R17, 185/65R15 and 195/65R15 as a planning band.
What is that in bar and kPa for the XD4?
Mid-points are about 2.31 bar (231 kPa) front and 2.31 bar (231 kPa) rear.
Should I bleed pressure after a motorway run?
No. Heat raises the gauge. Set cold only. Bleeding a hot tyre leaves it low the next morning.
Handbook: placard · bar vs PSI · front vs rear · cold inflation