The short answer
Start from the sticker on your door pillar. Lower the pressure in small steps, for the surface you are on, and reinflate before you get back onto sealed roads.
Starting points
- Sand and soft ground: about 15 to 17 psi
- Mud and rocks: about 20 to 22 psi
- Long gravel: about 20 to 23 psi
- Road: the placard figure, which is 26 psi for two people
Limits
- Do not go far below about 15 psi without beadlock wheels
- Too soft on rocks invites sidewall cuts
- Keep speeds low when aired down
- Reinflate before the road
Start with the placard
The maker's pressures are on a sticker on the door pillar. They are the right pressures for the road and for the car's weight, so everything else is a change from there.
| Situation | Front | Rear |
|---|---|---|
| Two people (Indian-market Jimny) | 26 psi | 26 psi |
| Fully loaded, four people (Indian-market Jimny) | 26 psi | 29 psi |
| Australian placard | 26 psi (180 kPa) | 26 psi (180 kPa) |
| psi | bar | kPa |
|---|---|---|
| 15 | 1.0 | 105 |
| 17 | 1.2 | 120 |
| 20 | 1.4 | 140 |
| 26 | 1.8 | 180 |
| 29 | 2.0 | 200 |
Check the sticker on your own car, since it can vary with market and tire size.
Starting points by terrain
| Terrain | psi | kPa | Notes |
|---|---|---|---|
| Road, two people | 26 | 180 | The placard figure. |
| Road, fully loaded | 26 front, 29 rear | 180 front, 200 rear | Heavy loads and high speeds need full pressure. |
| Long gravel | about 20 to 23 | 140 to 160 | Owners report much better comfort and fewer punctures. Keep speeds sensible. |
| Rough, rocky tracks | about 20 to 22 | 140 to 150 | Some give helps, but too soft risks sidewall cuts. |
| Mud | about 20 to 22 | 140 to 150 | Enough give for grip, enough support to protect the tires. |
| Sand and soft ground | about 15 to 17 | 105 to 120 | A 4x4 writer suggests about 120 kPa on standard tires for soft terrain. Owners report running down to 13 to 16 psi in sand. |
These figures come from the maker's placard and from owner and 4x4 community experience, not from a single test. Treat them as starting points and adjust.
Why it works, and where it stops
A lower pressure lets the tire flatten and spread, so the car floats over soft ground and the tire moulds around rocks. It also softens the ride and cuts the chance of punctures on rough roads. The trade-offs are real.
- The bead can come off the rim. Owners advise not going below about 14 to 15 psi on standard wheels without beadlocks, especially when turning hard.
- Sidewalls get cut. A soft tire on sharp rock is easy to slice, and a cut sidewall usually means a new tire.
- Speed has to drop. Owners who air down for sand keep to around 40 to 50 km/h. Aired-down tires heat up and flex a lot at speed.
- Pressure rises as tires warm. Check cold, and do not bleed a warm tire down to a cold target.
- Warnings. If your car has a pressure monitor, expect a low-pressure warning when you air down, and treat it as a reminder to reinflate.
Different tires, different pressures. Tires with heavier construction, such as C-load or LT types, often need higher pressures than the placard for the same load. Follow the tire maker's load and pressure table, and use the placard only as a base.
How to air down and back up
- Check cold pressures first. Note your starting figure for each tire.
- Release air in small steps. Lower all four tires evenly, checking with a gauge each time.
- Drive slowly and smoothly. Avoid hard braking and sharp steering, and watch for signs of being too low.
- Know the warning signs. A squirming tire, a bulging sidewall or a rim hitting the ground means the pressure is too low.
- Reinflate before sealed roads. Use a compressor, and do not rely on gas stations.
- Recheck cold at home. Check the spare too, since it is often forgotten.
The kit
- An accurate tire gauge that you trust
- A deflator, or a valve core tool
- A 12V compressor with enough hose to reach all four tires
- A tire repair kit, with plugs
- Spare valve caps and valve cores
Pick your pressure
Tap the surface to see a sensible starting pressure.
Tap a surface (6 to try)
Starting point for Road, two people
- Starting pressure
- -
- Why
- -
Common mistakes
- Dropping too far, too fast. Go in small steps and check.
- Driving fast on aired-down tires. They overheat and can fail.
- Forgetting to reinflate. Soft tires on tarmac wear, overheat and handle badly.
- Trusting a cheap gauge. A few psi of error matters at these pressures.
- Using one pressure everywhere. Surface, load and speed all change the answer.
- Going too soft on rocks. It invites sidewall cuts.
- Ignoring the spare. A flat spare is no help.
- Skipping the placard. Everything else starts from that figure.
A final word. Tire pressure affects handling and safety. These figures are general guidance drawn from the maker's placard and owner experience. Follow your tire maker's advice, your owner's manual and your own judgement, and always reinflate before driving at speed.