Thread: Sand tyre pressures

i never have to alter the tyre presuures on my shorty.

i have 30lb in them and they take me everywhere i want to go without a problem, except 45 degree slopes on wet grass [img]style_emoticons/<#EMO_DIR#>/tongue.gif[/img]

the lwb are a lot more sensitive to tyre pressures so i would be going with what the army markings recommend, the pressures may sound low but they arent for conventionals as they run at lower pressures than radials...

I struggled last time I was on sand, although that was pretty soft sand I reakon. Might set the stauns at what the plates say and see how I go :wink:

G'day,

245/70 X 16 HT down to 16 psi on Stockton's sand when soft and dry and for crossinghigh dunes.

20 psi for between low and high tide when damp

28 psi everywhere else and on road/gravel, lightly loaded

Cheers Scott. 8)

I live very close to some coastal sand dunes where it is actually permissable to drive on the sand and the beach. Acess is via a sandy track through the dunes.
I regularly witness idiots trying to drive over this track with too high pressures. The tell tale sign of too high tyre pressure is sand humps in the vehicle tracks caused by the wheels spinning.
Four wheel drive clubs appear to be the worst offenders- they think its macho to drive over this track without letting down the tyre pressures, and they leave deep gouges in the track behind them. They often get bogged and the drivers appear to be too stupid to let down their tyre pressure.
My son has a subaru and he lets his tyre pressure down to between 7-15psi depending on conditions and he drives around these bogged idiots. They cant believe it!
We use a general rule on the dunes- one PSI lower will get you one car length further up a dune. Im not talking about gouing up a freefall dune in this instance though.
Some people make a HUGE mistake in fitting wider tyres on their vehicles for sandy conditions. This makes things worse. Wide tyres create a wide barrier of sand in front of each tyre. A large diameter high walled narrow tyre is far better- it gives a long narrow footprint.

Originally posted by incisor
.... so i would be going with what the army markings recommend, the pressures may sound low but they arent for conventionals as they run at lower pressures than radials...

Be aware the army run Olympic Steeltreks .. radial tyres.

In the past I've found 18psi to be adequate for sand, unless you're really in the poo ... in which case you could drop down to about 12, but that's getting a tad risky as you may well loose the tyre off the bead.

Cheers

Except that I have rags, and the plackard has pressure valus for rags because that's what the vehicle was originally fitted with (bartreads).

That said, i've never taken radials below 18 PSI, although even that wasn't much on my retreads because they didn't have much flex.

Thanks for the ideas guys, I've got a pretty good idea how low I want to drop the tyres now :wink:

Has anyone fitted 255/85/16's to their Defender? Any issues?
I am considering doing it in preference to going to 265/75/16's when my tyres are due for a change.
The 255's will give a 4.2% change in speedo error. ie when doing 96 on the speedo the car will be doing approx 100 klms/hr. This should lower the engine revs a little bit. The wheel will also rotate about 2000 revs less per hour. (Opposite Lock have a handy calc in their computer which gives this stuff).
Cheers.

Posted here because of 10 attempts to post a new topic failed!
(invalid session).

I have been known to go as low as 8psi on BFG muds.

Did fraser in 2wd at that tyre presure