235/45R17 · passenger car · PSI
235/45R17 tyre pressure in PSI
- Size
- 235/45R17
- Class
- passenger car
- Planning PSI
- 36
- Planning bar
- 2.48
psi
36
2.48 bar · 248 kPa · passenger car planning figure
235/45R17 · 36 psi · 2.48 bar · 248 kPa — estimates. Placard wins.
If someone typed “235/45R17 psi”, they want Imperial. Start near 36 psi on an unladen passenger car, then confirm the vehicle placard. Sidewall max is not the target. Under-inflation cooks the shoulders of a 235/45R17; over-inflation wears the centre rib and bangs every cat’s eye. Low-profile {sz} does not want a “softer” pressure to recover ride. Stay at or slightly above the car’s original placard if load index is kept.
Estimated 235/45R17 pressure by load
Plus-sizing to 235/45R17 from a taller OEM tyre usually keeps the same placard if the load index is equal or higher.
| Condition | Front (est.) | Rear (est.) |
|---|---|---|
| Driver only / unladen | 36 psi / 2.48 bar / 248 kPa | 36 psi / 2.48 bar / 248 kPa |
| Typical occupancy | 36 psi / 2.48 bar / 248 kPa | 37 psi / 2.55 bar / 255 kPa |
| Motorway + luggage (sketch) | 37 psi / 2.55 bar / 255 kPa | 38 psi / 2.62 bar / 262 kPa |
PSI, bar and kPa
Use the table, then set a cold gauge. 248 kPa is 100 × 2.48 bar on this size.
| PSI | Bar | kPa |
|---|---|---|
| 32 | 2.21 | 221 |
| 33 | 2.28 | 228 |
| 34 | 2.34 | 234 |
| 35 | 2.41 | 241 |
| 36 | 2.48 | 248 |
| 37 | 2.55 | 255 |
| 38 | 2.62 | 262 |
| 39 | 2.69 | 269 |
| 40 | 2.76 | 276 |
| 41 | 2.83 | 283 |
| 42 | 2.90 | 290 |
| 43 | 2.96 | 296 |
| 44 | 3.03 | 303 |
| 45 | 3.10 | 310 |
| 46 | 3.17 | 317 |
| 47 | 3.24 | 324 |
| 48 | 3.31 | 331 |
What 235/45R17 means
A 235/45R17 on a passenger car is a geometry. Two cars can share the size and disagree on PSI because mass and axle split differ.
Wide 17-inch sport. Rim diameter 17 in; section 235 mm. Estimates on this page assume a typical load index for the passenger car class.
Placard versus sidewall
This website maps size searches such as “235/45R17 psi”. It does not replace the VIN label. If the two disagree, the label wins.
Cars often seen on 235/45R17
These catalogue models are often seen on 235/45R17 or a close OEM neighbour. Open the vehicle chart for axle-specific PSI and bar.
How to set 235/45R17
- Park so the 235/45R17 tyres are cold (three hours, or less than about a mile).
- Read the door-pillar placard for that car — not the 235/45R17 sidewall maximum.
- If the sticker is missing, 36 psi / 2.48 bar is only a passenger car planning figure for this size.
- Set all four with a calibrated gauge. A 3 psi miss on one corner shows up as a wander.
- Refit valve caps and reset TPMS if the handbook asks for a relearn.
Temperature drift
Roughly 1 psi per 5–6 °C. The table uses 36 psi as a 20 °C baseline for 235/45R17.
| Ambient | Gauge | Bar | kPa | Note |
|---|---|---|---|---|
| −5 °C (hard frost) | 33 psi | 2.28 bar | 228 kPa | Gauge reads low; do not overfill once warm |
| 0 °C | 34 psi | 2.34 bar | 234 kPa | Gauge reads low; do not overfill once warm |
| 8 °C (UK winter morning) | 35 psi | 2.41 bar | 241 kPa | Gauge reads low; do not overfill once warm |
| 20 °C (set cold here) | 36 psi | 2.48 bar | 248 kPa | Baseline for this size sketch |
| 30 °C | 38 psi | 2.62 bar | 262 kPa | Do not bleed a hot 235/45R17 |
| 38 °C (heatwave tarmac) | 39 psi | 2.69 bar | 269 kPa | Do not bleed a hot 235/45R17 |
A cheap gauge and a monthly habit will do more for a set of 235/45R17 than nitrogen upsells.
Questions about 235/45R17
What is 235/45R17 in kPa?
248 kPa is the planning midpoint (100 kPa = 1 bar). 255 kPa is one PSI higher.
Is 235/45R17 the same as a plus-size swap?
Only if that is the size you fitted. Overall diameter should stay close to OEM. Pressure still follows the car, with load index at or above original.
What PSI should 235/45R17 tyres be?
A passenger car planning figure is about 36 psi cold (2.48 bar / 248 kPa). Confirm on the vehicle placard — two cars can share 235/45R17 and not share a sticker.
Is the sidewall number correct for 235/45R17?
No. Sidewall PSI or kPa is a maximum for the carcass. Operating pressure is the door-pillar placard.
When does TPMS warn on 235/45R17?
Direct TPMS typically flags about 25% below target — near 27 psi if you were aiming at 36. Fill to the sticker, not to the lamp.
Handbook: placard · bar vs PSI · cold inflation · all sizes