<span class="highlight">Tyre</span> pressure for Simpson

Thankyou.

Thanks for the hot tip

Just seen Brian's contribution, and I agree with him. Selecting the right gear, right speed, learning to handle the dunes (especially the bit at the top) are all essential to a happy trip. No article in a 4x4 mag can substitute for training (in my case, in situ, with an old pro).

Thanks Chris

You assume wrong, plenty of treks but I just needed the surface type on this crossing but cut to the chase and asked the pressures instead, but thanks for the info.

Cheers

Very good answer - I consider myself a bit of a past master on sand driving, but would approach the Simpson very much as a novice (driving there for the first time in September, via the Birdsville Races), so advice like this I would closely listen to.

Be aware that the lower the pressure the easier it is to drive on sand and the less strain you put on the drivetrain, AND the slower you should go, AND the greater the danger of spinning the rim inside the tyre.

I start of at 22, and adjust down to 16 if required, though that has to be loose dry sand if I go that low. I adjust down in increments of 2 psi, and may take 14 psi if need be - 12 psi is pushing it

10 psi for emergencies only - the risk of spinning the rim or damaging the tyre is high - however it will get you out trouble probably quicker than any other method.

viz

Viz,
You will find desert sand driving driving different to whatever sand driving you've done before, so I personally would not do as you suggest.

Like Stephen, I love the desert country and have done a lot of trips out there over the past 30 odd years, and I agree 100% with his suggestions.

You seem concerned about lowering tyre pressures too far. But for Simpson Desert travel its best to start at lower pressures because past experience says it works out there - and in addition, you'll find your vehicle will be working easier, it will use less fuel and you can drive the dunes more slowly - many of the approaches are deeply scalloped from vehicles running too much air, and if you take them too fast, you will do damage - not just suspension, but I've seen dual cabs with bent chassis from taking these dunes too fast. Most vehicles are loaded to the hilt out there.

I have never seen a vehicle roll a tyre off a rim in the desert. But I've seen it countless times close to home - at places like Peake and Beachport where our 4wd clubs teach sand driving.

Tyre damage is most likely to occur when travelling to and from the desert - the bigger sharp stones on the Oodnadatta, Birdsville and Pedirka tracks will easily penetrate the tread if you travel too fast, with too much pressure, too much weight or with tyres that are >50% worn. Its rare to damage a tyre on the central tracks in the Simpson Desert.

One of the reasons that I participate in forums like this - genuine gold this advice.

Thanks for that.

I am not in disagreement with your advice at all - what initial tyre pressures would you go down to for dune travelling? Considering that my Cruiser has 285/75s which is a bloody huge footprint :)

I have a love for the desert too, but have yet done little serious travel in it. I mainly have flown planes over it and/or landed at outback stations or towns, then gone driving somewhere. This time around I want to have some serious looking at places that I have flown over, without biting off more than I can chew.

Nothing beats (for me) swagging under the stars in the desert on a clear night...

Well, almost nothing - better if someone is in the swag with you ;)

viz

Viz,
Most of my recent travel has been on 265/75 but I now run 285/75 as well.

I run 24F/28R as soon as I leave the bitumen, and limit the speed to 80kph.

I air down to 16F/20R when you reach the dunes near Purnie Bore in the west or Big Red in the east. The only times I've gone lower was when the dunes were very soft after a hot dry summer and when I was running Goodyear MTRs which don't air down as well as other tyres.

Cheers
Phil

Hi Viz
The bigger the foot print, the better. Like Phil has said above, on the normal travelled tracks over the Simpson, we have never had any tyre trouble what so ever ( I will not comment on the cross country trip, pure virgin dunes, some real big mothers. Side wall punctures were the norm. Our record was 2 days in a row with no puncture at all out of 15 days) If it is your first trip to the Simpson, 16 psi will be great starting point. You are only travelling slow, usually 3rd high and between 30 - 40 kilometres per hour, sometimes slower. It is not a race, take your time, there is lots to see. On one of our east / west crossings a good number of years ago, we zig zagged all over the desert and spent 8 nights enjoying the Simpson Desert solitude.

Cheers

Stephen

Excellent stuff. Thanks

That reminds me!! The first time I drove the Simpson in my Prado, I heeded the advice to use High 1st, and because of the petrol V6 engine, and my beliefs about its torque curve, I kept the revs up around 3000 rpm. The first big dune we met up with showed the ability of a loaded Prado to become literally airborne!!
When you think about it, high 1st at 3000 is around 35 plus kph, a bit much for a sharp dune crest.
These days, I tend to use low 3rd for the sharper dunes, approach at around 2700 rpm, and then let it fall back to around 1000 rpm or less at the crest, or a speed in the teens.
I know that Stephen was not suggesting 30 plus regardless, but his words just triggered memories of a very interesting experience!!

Hi Chris, I have not taken my Prado diesel through the Simpson yet, but from situations like you have outlined, this is why I prefer a diesel. With our old 2.8 Pajero, I would uses 1st High, but just idle up at just over 1600 rpm, because as you know, loose your torque with a petrol vehicle, it is a very quick gear change and hope that you do not get bogged. In relation to the speed, I should have stated in the swales that speed is usually 30 - 40 kilometres per hour and always approach all dunes with caution. Speed at the top of a dune and a vehicle approaching from the other way without a sand flag will lead to a situation that I would not like to see.

Cheers

Stephen