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DiscoSaffa
2nd December 2009, 11:53 AM
Having just filled up with fuel and pumped up my tyres, I have a question……. And a moan

Why do tyre manufacturers specify cold temperatures, I understand the need for consistency etc, but in reality one almost NEVER checks one’s tyres when they are cold….. the shortest drive to the servo will warm them to a point…. So this figure is generally useless and will leave your tyres underinflated

Does anyone know what the warm tyre pressures are for a D3, relating to the unladen cold pressure of 230kPa front and 250kPa rear? I tend to allow around 30kPa for temperature and base this on nothing other than gut feel.

I am running the standard 18 inch wranglers (soon to be changed). What sort of pressures do you guys and girls normally run?

Thanks in advance

big guy
2nd December 2009, 01:45 PM
I run 38PSI all round.
My mate has sensors in all wheels and I am amazed by how much they change whilst running and if the sun is on them on one side or not or if in sand, wet beach sand or dark bitumen roads.
They spiked at 49psi at one point on one side.
That tyre than copped a punture on a run to Morgan from Adelaide as he went from bitumen to gravel.
Only the front tyre blew.
Tyre shop claimed it was overinflated and he should have let his pressures down which I guess he was right.
They did check pressures and sure enough they were all back down to 38 again.

Thats probably why Coopers get such a hiding because we are not aware of what is going on with pressures in our tyres and they could be more prone to pressure variation.

jonesfam
2nd December 2009, 01:59 PM
WHY do we nearly all still speak in PSI when Australia has been metric since 1974?
I admit I do, like I still know how big a house is in squares or land in acres.
Strange.
Jonesfam

Bushwanderer
2nd December 2009, 02:33 PM
DiscoSaffa,
Depending on how warm your tyres are when checking, inflate them by 2-4 psi above the cold reading. Then when cold check & adjust the pressures again (you do have a tyre pressure gauge don't you?).

Alternatively, before you start off, check the pressures and then when at the S/S add any required extra.

Thirdly, have a compressor in your car and check and adjust pressures before you start out.

HTH,
Peter

DiscoSaffa
8th December 2009, 08:06 AM
(you do have a tyre pressure gauge don't you?).

Of course I do..... only problem is, it is currently sitting in the boot of my DII in South Africa..... I hope the new owner is enjoying it....... Compressor and gauge onto my stocking filler list for Santa....... Oh and after this morning's debacle, a set of jumper leads........ :mad: