One of the most important concepts surrounding four wheel driving is the tyre pressures that you run. The moment you leave the bitumen, your tyre pressures need to be adjusted accordingly. This helps by increasing traction, using less fuel and preserving the tracks, tyres and car mechanicals.
How do you get more traction from lower tyre pressures?
When you let air out of your tyres, the footprint (the rubber that is touching the ground) grows. It grows in both width and in length. The growth in length is what provides the most additional traction, which is why taller tyres are better for four wheel driving.
How can you let your tyres down?
If you very rarely go off road, a stick or key pressed onto the end of the air valve will deflate the tyres. However, it takes a while to let each tyre down, and I am quite impatient! Staun deflators have been very popular in the past; you simply remove the valve cap, screw the staun on and it will let your tyre down to a pre set pressure. Alternatively, you remove the valve stem and the air rushes out. This can be done with a number of tools, with the ARB Deflator being the most well known and reputable one on the market.
What are the right tyre pressures?
The right tyre pressures are determined by the weight of your vehicle, terrain being driven on and size of the tyres. The larger the tyres, the less pressure required. As a general rule of thumb, gravel should see your tyres let down to 20 – 28 PSI. Mud and rocks should see 15 – 20 PSI, and beach driving should be 12 – 15 PSI. There are exceptions to this, but in majority of the cases these pressures will look after your tyres, preserve the tracks and ensure you minimize and chance of mechanical failure.
My review of deflators
I’ve tried all sorts of deflators, from standing there with a small stick through to stauns, ferret deflators, pressure gauge deflators and have finally ended up with the ARB deflator. There really is no comparison; it just works, and works well! I don’t like the staun deflators, because they take some time to pre set, and are well known to rattle loose and change pressures. A few people carry several sets, but by the time you add the costs up it just isn’t worth it.
About the ARB Deflator
For $70, you can purchase a genuine ARB Deflator. At the shows (and sometimes online) you will get them for slightly cheaper. They simply screw onto the valve, and then you unscrew the valve stem. By moving a sleeve back and forth it will either rapidly deflate the air, or tell you what pressure is left in the tyre. This gives you an accurate indication, and confirmation that each tyre is let down to exactly the same pressure. It only takes a few minutes to do all 4 tyres, and you don’t have to kneel down for the whole time you are deflating.
Obviously, you don’t need a deflator. However, one soon gets sick of kneeling down poking a stick into the valve for minutes on end!; you can’t go passed the ARB Deflator.