Thread: L660 or L663

I agree with John. “...sand driving is about 60% driver, 30% tyre pressure and 10% vehicle.” The 10% vehicle relates primarily to ground clearance and weight of the vehicle.

Originally Posted by blackrangie

Good for a laugh "i got bogged at inskip" facebook page, i Googled the other day. Nearly every type of 4x4 under the sun gets bogged or breaks. I would say tyre pressures and momentum are the biggest causes, which are both driver error.
New defender if it has CTIS will help the newbies

Yes view that page regularly.....pretty much every example is 100% tyre pressure, I’ve rarely thought that I needed extra momentum, air down and cruise along.

Low tyre pressure means pretty much anybody and or 4WD will be fine.

Yep it is all tire pressure. That said a lighter vehicle with bigger tyres can run lower pressures.

Originally Posted by Red90

Yep it is all tire pressure. That said a lighter vehicle with bigger tyres can run lower pressures.

You mean lower pressure drop mate?

Less weight on a bigger tyre means you can run a lower pressure.

Originally Posted by DiscoClax

Less weight on a bigger tyre means you can run a lower pressure.

Would it also mean you could run higher pressures, as your just sitting on top of the sand?

We run 35s on 16x10s ususlly between 2.7t to 3t on sand and sit between 16 and 20psi depending how soft.

Well pressure is really just force divided by area. Force=weight in this case. Area=Tyre volume. Huge tyres = low pressures required. Low weight = low pressures required. Both combined = super low pressures required. Reverse also true
BTW I'm not saying that 3t is low weight. Just an example. Have a look at the load rating of your 35s and at what pressure and then scale that back to 750kg per corner and see what pressure you need with to hold the car up... *simplistic example for the purposes of illustrating the concept. Actual tyre load curve is not linear to zero.
The 31x10.5s on my little 7x5' box trailer I run at about 14psi when lightly laden. With a tonne of dirt in it I'll take them up to low 20s. And that's ample.
Hay River Track last year in the Disco (heavy wall 235/85s) I ran as low as 10/12psi over the Simpson dunes no worries. Ran 16/18psi on the track itself. And we were very heavily loaded. Others we travelled with decided on highway pressures and they got bogged (a lot) and stuff got smashed. Last time I (stupidly) ran around 22psi across the dunes on fatter 265/75s and had to work at it and carry speed. This time just walked up each one leisurely in comfort. And we went the harder way this time...

Originally Posted by DiscoClax

Well pressure is really just force divided by area. Force=weight in this case. Area=Tyre volume. Huge tyres = low pressures required. Low weight = low pressures required. Both combined = super low pressures required. Reverse also true
BTW I'm not saying that 3t is low weight. Just an example. Have a look at the load rating of your 35s and at what pressure and then scale that back to 750kg per corner and see what pressure you need with to hold the car up... *simplistic example for the purposes of illustrating the concept. Actual tyre load curve is not linear to zero.
The 31x10.5s on my little 7x5' box trailer I run at about 14psi when lightly laden. With a tonne of dirt in it I'll take them up to low 20s. And that's ample.
Hay River Track last year in the Disco (heavy wall 235/85s) I ran as low as 10/12psi over the Simpson dunes no worries. Ran 16/18psi on the track itself. And we were very heavily loaded. Others we travelled with decided on highway pressures and they got bogged (a lot) and stuff got smashed. Last time I (stupidly) ran around 22psi across the dunes on fatter 265/75s and had to work at it and carry speed. This time just walked up each one leisurely in comfort. And we went the harder way this time...

Cheers good info