LT275/70R18 · LT-metric truck · Bar
LT275/70R18 bar chart (3.86 bar planning figure)
- Size
- LT275/70R18
- Class
- LT-metric truck
- Planning PSI
- 56
- Planning bar
- 3.86
bar
3.86
56 psi · 386 kPa · not a second factory sticker
LT275/70R18 · 56 psi · 3.86 bar · 386 kPa — estimates. Placard wins.
A LT275/70R18 C-type or LT carcass can live far above a hatchback bar figure. This page’s 3.86 bar sketch is for the LT-metric truck class, not every car that can physically mount the tyre. A 10 °C overnight drop takes roughly 1 psi (0.07 bar) off a closed LT275/70R18. LT-metric sizes print a load range. The vehicle door sticker, not the LT sidewall maximum, is still the operating pressure.
Bar, PSI and kPa
Use the table, then set a cold gauge. 386 kPa is 100 × 3.86 bar on this size.
| Bar | PSI | kPa |
|---|---|---|
| 3.03 | 44 | 303 |
| 3.17 | 46 | 317 |
| 3.45 | 50 | 345 |
| 3.59 | 52 | 359 |
| 3.65 | 53 | 365 |
| 3.72 | 54 | 372 |
| 3.79 | 55 | 379 |
| 3.86 | 56 | 386 |
| 3.93 | 57 | 393 |
| 4.00 | 58 | 400 |
| 4.07 | 59 | 407 |
| 4.14 | 60 | 414 |
| 4.21 | 61 | 421 |
| 4.27 | 62 | 427 |
| 4.34 | 63 | 434 |
| 4.41 | 64 | 441 |
| 4.48 | 65 | 448 |
| 4.55 | 66 | 455 |
| 4.62 | 67 | 462 |
| 4.69 | 68 | 469 |
| 5.52 | 80 | 552 |
Estimated LT275/70R18 pressure by load
These LT275/70R18 load steps are ± a few PSI from 56. They are not a licence to ignore a printed second column on a van or estate.
| Condition | Front (est.) | Rear (est.) |
|---|---|---|
| Driver only / unladen | 56 psi / 3.86 bar / 386 kPa | 58 psi / 4 bar / 400 kPa |
| Typical occupancy | 56 psi / 3.86 bar / 386 kPa | 59 psi / 4.07 bar / 407 kPa |
| Payload / towing (sketch) | 57 psi / 3.93 bar / 393 kPa | 66 psi / 4.55 bar / 455 kPa |
Placard versus sidewall
This website maps size searches such as “LT275/70R18 psi”. It does not replace the VIN label. If the two disagree, the label wins.
What LT275/70R18 means
Read LT275/70R18 as width / aspect R rim. Nothing in the size string is a pressure. Pressure lives on the car, not moulded as 205 or 55.
Plus-size LT 18-inch. Rim diameter 18 in; section 275 mm. Estimates on this page assume a typical load index for the LT-metric truck class.
Cars often seen on LT275/70R18
These catalogue models are often seen on LT275/70R18 or a close OEM neighbour. Open the vehicle chart for axle-specific PSI and bar.
How to set LT275/70R18
- Park so the LT275/70R18 tyres are cold (three hours, or less than about a mile).
- Read the door-pillar placard for that car — not the LT275/70R18 sidewall maximum.
- If the sticker is missing, 56 psi / 3.86 bar is only a LT-metric truck 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 56 psi as a 20 °C baseline for LT275/70R18.
| Ambient | Gauge | Bar | kPa | Note |
|---|---|---|---|---|
| −5 °C (hard frost) | 53 psi | 3.65 bar | 365 kPa | Gauge reads low; do not overfill once warm |
| 0 °C | 54 psi | 3.72 bar | 372 kPa | Gauge reads low; do not overfill once warm |
| 8 °C (UK winter morning) | 55 psi | 3.79 bar | 379 kPa | Gauge reads low; do not overfill once warm |
| 20 °C (set cold here) | 56 psi | 3.86 bar | 386 kPa | Baseline for this size sketch |
| 30 °C | 58 psi | 4 bar | 400 kPa | Do not bleed a hot LT275/70R18 |
| 38 °C (heatwave tarmac) | 59 psi | 4.07 bar | 407 kPa | Do not bleed a hot LT275/70R18 |
Keep LT275/70R18 on the printed band for that car; 56 psi is a size sketch, not a second VIN label.
Questions about LT275/70R18
Is the sidewall number correct for LT275/70R18?
No. Sidewall PSI or kPa is a maximum for the carcass. Operating pressure is the door-pillar placard.
When does TPMS warn on LT275/70R18?
Direct TPMS typically flags about 25% below target — near 42 psi if you were aiming at 56. Fill to the sticker, not to the lamp.
Can I run LT275/70R18 at a lower pressure for comfort?
Not as a habit. A soft LT275/70R18 cooks the shoulders and dulls steering. Keep load index and stay on the placard.
What is LT275/70R18 in bar?
56 psi is 3.86 bar. Add a tenth of a bar if the placard’s laden column is higher, which is common on vans that wear this size.
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 · cold inflation · all sizes