Thread: Tyre pressures

Good question, I haven't got around to getting 18's for mine yet, but it is on the list, so this is an answer I would like to know as well. Your guess sounds about right, hope someone else here can confirm this.

Cheers - Gav

Hi, I travelled Odnadatta Tk, Ghan track, Cobourg Rd and Gulf road last year on 255/60/18 GG's, kept pressure to 26/7 psi, without any drama. I do try to keep speed down over rocky sections and was worried about depth of rubber between road and rim. I have now fitted a set of 65 profile BFG's for my next trip to give me a little more peace of mind. I was unable to get any reliable info on recommended pressures before making the trip last year and arrived at my conclusion by looking at tyre clearance at different pressures before settling on 26 etc. I will have to do the exercise all over for the BFG's unless someone else has any ideas ? Also I tow a trailer so the car did not have a lot of weight in the rear.
Cheers, Peter

Hi Guys,

Thought I'd weigh in on this one as well. I tend to keep my normal road going pressures at around the 36-40psi mark depending upon end and load. This is according to the placard and tyre manufacturer recommendations.

According to the latest information from Land Rover the pressures should not be lowered below 80% of the placard pressure for tyres with a profile of 60% or less.

This means that if your rear tyres are at 40 psi then they can be brought back to 32psi, the fronts from 30psi down to 24psi. This may be conservative based on conventional thinking but it should provide a fair safety margin to help reduce the likelihood of pinching the tyre and rim. Sand is a whole different ball game but even then anything below 24psi is asking for trouble with the possibility of separation from the rim getting greater exponentially with every pound less.

I travelled for a couple of weeks through the Flinders Ranges and parts north to Lake Eyre last year and had my pressures around the 26-30psi mark depending on the terrain without a single hiccup. I may have been lucky. That was on GG AT2s (255/60R18).

Of course the old maxim still applies. The tyre pressure comes down, the vehicle speed comes down accordingly.

I personally work to a simple 75% rule as the math is mostly easy (3/4x). I never go below this unless in dire times.

That's my 5c worth anyway.

Cheers,
Iain