BMW · M8 · Recommended
Recommended tyre pressure for a BMW M8
- 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
psi
34 / 34
Catalogue mid-points, front / rear · 2.2-2.4 / 2.2-2.4 bar
32-35 psi F · 32-35 psi R · 2.2-2.4 / 2.2-2.4 bar · 231/231 kPa
Treat this page as a map of the M8 band. The legal setpoint is the printed door-pillar label for your VIN. A 10 °C overnight drop takes roughly 1 psi (0.07 bar) off a closed BMW tyre.
How to set the M8
- Measure before the school run, not after the M25.
- Write LF / RF / RR / RL. Do not keep M8 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.
BMW M8 placard versus sidewall
If the BMW sticker is painted over, the handbook is next. This website is a map, not a replacement VIN label.
Estimated pressure by tyre size (225/45R17 and others)
225/45R17 is the first planning size here. 255/40R17 is usually the plus-size or LT step. Keep load index at or above original equipment.
| Tyre size | Front PSI | Rear PSI | Front bar | Rear bar | Front kPa | Rear kPa | Note |
|---|---|---|---|---|---|---|---|
| 225/45R17 | 34 | 35 | 2.34 | 2.41 | 234 | 241 | Front sport size |
| 275/30R19 | 36 | 37 | 2.48 | 2.55 | 248 | 255 | Rear 19-inch |
| 255/40R17 | 35 | 36 | 2.41 | 2.48 | 241 | 248 | Rear stagger 17-inch |
| 245/40R18 | 35 | 36 | 2.41 | 2.48 | 241 | 248 | Square-ish sport |
| 255/35R18 | 35 | 36 | 2.41 | 2.48 | 241 | 248 | Rear stagger 18-inch |
| 275/35R18 | 36 | 37 | 2.48 | 2.55 | 248 | 255 | Wide rear |
| 235/35R19 | 36 | 36 | 2.48 | 2.48 | 248 | 248 | Front 19-inch |
| 225/40R18 | 35 | 35 | 2.41 | 2.41 | 241 | 241 | Front 18-inch |
PSI, bar and kPa
PSI-led conversions for the BMW M8 band (32-35 / 32-35).
| PSI | Bar | kPa |
|---|---|---|
| 30 | 2.07 | 207 |
| 32 | 2.21 | 221 |
| 33 | 2.28 | 228 |
| 33.5 | 2.31 | 231 |
| 35 | 2.41 | 241 |
| 36 | 2.48 | 248 |
| 38 | 2.62 | 262 |
| 40 | 2.76 | 276 |
| 44 | 3.03 | 303 |
| 50 | 3.45 | 345 |
| 60 | 4.14 | 414 |
Pressure against load
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 | 36 psi / 2.48 bar |
Temperature drift
Roughly 1 psi per 5–6 °C. The table uses 34 psi as a 20 °C baseline for this M8.
| 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 |
BMW notes
BMW run-flats still want the placard. Comfort settings in the iDrive do not replace the door-pillar figure on this M8.
Spare and inflator kit
A matching full-size spare on the BMW M8 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.
Keep the BMW M8 on the printed band; use 225/45R17 and 255/40R17 only as a map for non-OEM wheels.
Other BMW models
Questions about this M8
What PSI if I plus-size toward 255/40R17?
Keep load index at or above OEM. Low-profile sizes usually stay at or slightly above the placard. Use 225/45R17, 275/30R19 and 255/40R17 as a planning band.
What is that in bar and kPa for the M8?
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.
How often should I check a M8?
Monthly, before a long trip, and after a 10 °C weather swing. Include a full-size spare.
Front versus rear on the BMW M8?
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.
Handbook: placard · bar vs PSI · front vs rear · cold inflation