255/45R19 · SUV / crossover · PSI
What PSI for 255/45R19 tyres?
- Size
- 255/45R19
- Class
- SUV / crossover
- Planning PSI
- 36
- Planning bar
- 2.48
psi
36
2.48 bar · 248 kPa · SUV / crossover planning figure
255/45R19 · 36 psi · 2.48 bar · 248 kPa — estimates. Placard wins.
If someone typed “255/45R19 psi”, they want Imperial. Start near 36 psi on an unladen SUV / crossover, then confirm the vehicle placard. Sidewall max is not the target. A 10 °C overnight drop takes roughly 1 psi (0.07 bar) off a closed 255/45R19.
Estimated 255/45R19 pressure by load
These 255/45R19 load steps are ± a few PSI from 36. They are not a licence to ignore a printed second column on a van or estate.
| Condition | Front (est.) | Rear (est.) |
|---|---|---|
| Driver only / unladen | 36 psi / 2.48 bar / 248 kPa | 37 psi / 2.55 bar / 255 kPa |
| Typical occupancy | 36 psi / 2.48 bar / 248 kPa | 38 psi / 2.62 bar / 262 kPa |
| Motorway + luggage (sketch) | 37 psi / 2.55 bar / 255 kPa | 39 psi / 2.69 bar / 269 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 255/45R19 means
255/45R19 means a 255 millimetre section width, a sidewall that is 45 percent of that width, on a 19-inch rim. The R is radial construction.
19-inch SUV plus-size. Rim diameter 19 in; section 255 mm. Estimates on this page assume a typical load index for the SUV / crossover class.
Placard versus sidewall
If a forum says “all 255/45R19 run 36 psi”, ignore it. A Qashqai and a Golf can share a size and not share a sticker.
Cars often seen on 255/45R19
These catalogue models are often seen on 255/45R19 or a close OEM neighbour. Open the vehicle chart for axle-specific PSI and bar.
How to set 255/45R19
- Measure before the school run, not after the motorway.
- Write LF / RF / RR / RL. Do not keep 255/45R19 numbers in your head.
- Add air in short bursts toward the placard, using 36 psi only as a map.
- If one 255/45R19 is 4 psi down, hunt for a nail before you blame the weather.
- Log date, ambient temperature and the four readings.
Temperature drift
Roughly 1 psi per 5–6 °C. The table uses 36 psi as a 20 °C baseline for 255/45R19.
| 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 255/45R19 |
| 38 °C (heatwave tarmac) | 39 psi | 2.69 bar | 269 kPa | Do not bleed a hot 255/45R19 |
If the door sticker and this 255/45R19 page disagree, the sticker wins.
Questions about 255/45R19
Can I run 255/45R19 at a lower pressure for comfort?
Not as a habit. A soft 255/45R19 cooks the shoulders and dulls steering. Keep load index and stay on the placard.
When does TPMS warn on 255/45R19?
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.
What PSI should 255/45R19 tyres be?
A SUV / crossover planning figure is about 36 psi cold (2.48 bar / 248 kPa). Confirm on the vehicle placard — two cars can share 255/45R19 and not share a sticker.
Is 255/45R19 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 is 255/45R19 in kPa?
248 kPa is the planning midpoint (100 kPa = 1 bar). 255 kPa is one PSI higher.
Handbook: placard · bar vs PSI · cold inflation · all sizes