UK · EU reference Tyre Pressure

205/40R17 · passenger car · kPa

205/40R17 kPa inflation table

Size
205/40R17
Class
passenger car
Planning PSI
35
Planning bar
2.41

kPa

241

2.41 bar · 35 psi · 100 kPa = 1 bar

205/40R17 · 35 psi · 2.41 bar · 241 kPa — estimates. Placard wins.

Kilopascals show up on some Asian stickers and ISO sheets. 241 kPa is the planning midpoint for 205/40R17 (2.41 bar / 35 psi). 100 kPa = 1 bar. TPMS typically warns near 26 psi (about 25% below a 35 psi target). That is already a soft tyre. 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.

kPa, bar and PSI

1 bar ≈ 14.5 psi; 1 psi ≈ 6.89 kPa. Planning midpoint for 205/40R17: 35 psi = 2.41 bar = 241 kPa.

kPaBarPSI
2142.1431
2212.2132
2282.2833
2342.3434
2412.4135
2482.4836
2552.5537
2622.6238
2692.6939
2762.7640
2832.8341
2902.9042
2962.9643
3033.0344
3103.1045
3173.1746
3243.2447

Estimated 205/40R17 pressure by load

These 205/40R17 load steps are ± a few PSI from 35. They are not a licence to ignore a printed second column on a van or estate.

ConditionFront (est.)Rear (est.)
Driver only / unladen35 psi / 2.41 bar / 241 kPa35 psi / 2.41 bar / 241 kPa
Typical occupancy35 psi / 2.41 bar / 241 kPa36 psi / 2.48 bar / 248 kPa
Motorway + luggage (sketch)36 psi / 2.48 bar / 248 kPa37 psi / 2.55 bar / 255 kPa

What 205/40R17 means

205/40R17 means a 205 millimetre section width, a sidewall that is 40 percent of that width, on a 17-inch rim. The R is radial construction.

Very low 17-inch compact. Rim diameter 17 in; section 205 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 “205/40R17 psi”. It does not replace the VIN label. If the two disagree, the label wins.

Temperature drift

Roughly 1 psi per 5–6 °C. The table uses 35 psi as a 20 °C baseline for 205/40R17.

AmbientGaugeBarkPaNote
−5 °C (hard frost)32 psi2.21 bar221 kPaGauge reads low; do not overfill once warm
0 °C33 psi2.28 bar228 kPaGauge reads low; do not overfill once warm
8 °C (UK winter morning)34 psi2.34 bar234 kPaGauge reads low; do not overfill once warm
20 °C (set cold here)35 psi2.41 bar241 kPaBaseline for this size sketch
30 °C37 psi2.55 bar255 kPaDo not bleed a hot 205/40R17
38 °C (heatwave tarmac)38 psi2.62 bar262 kPaDo not bleed a hot 205/40R17

How to set 205/40R17

  1. Measure before the school run, not after the motorway.
  2. Write LF / RF / RR / RL. Do not keep 205/40R17 numbers in your head.
  3. Add air in short bursts toward the placard, using 35 psi only as a map.
  4. If one 205/40R17 is 4 psi down, hunt for a nail before you blame the weather.
  5. Log date, ambient temperature and the four readings.

Cars often seen on 205/40R17

These catalogue models are often seen on 205/40R17 or a close OEM neighbour. Open the vehicle chart for axle-specific PSI and bar.

If the door sticker and this 205/40R17 page disagree, the sticker wins.

Questions about 205/40R17

Is 205/40R17 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.

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.

Is the sidewall number correct for 205/40R17?

No. Sidewall PSI or kPa is a maximum for the carcass. Operating pressure is the door-pillar placard.

What PSI should 205/40R17 tyres be?

A passenger car planning figure is about 35 psi cold (2.41 bar / 241 kPa). Confirm on the vehicle placard — two cars can share 205/40R17 and not share a sticker.

Can I run 205/40R17 at a lower pressure for comfort?

Not as a habit. A soft 205/40R17 cooks the shoulders and dulls steering. Keep load index and stay on the placard.

Handbook: placard · bar vs PSI · cold inflation · all sizes