Tyre Pressures - what do you run?

[Kev7762 Senior Member Find all posts View Profile Close Kev7762]

Same for me still on the standard Grandtreks 55k's now generally run 40 on the rear and 38 on the front, drop to 28ish on gravel and 18 in the sand.
Tyres are rotated including spare, front to rear, side to side as per manual every 5k, still have about 5-6 mm in the centres although the edges are worn, some worse than others.

[davesomma Junior Member Find all posts View Profile Close davesomma]

Hey there all
Just got back from Elliston on the Eyre Peninsular and for the trip i started out with 34 PSI in my Cooper ST MAXX and noticed on the trip over i was getting up to 8 PSI increase when running on the roads in the rear set and about 6 PSI difference in the front. I used a tyredog setup to keep an eye on them for the whole trip.

Food for thought

Cheers

[Dueler120 Senior Member Find all posts View Profile Close Dueler120]

G'day,
Hope this might help;

http://www.slippersopreis.nl/mediapo...e_pressure.pdf

Cheers,

[davesomma Junior Member Find all posts View Profile Close davesomma]

good guide thanks for that

[fido666 Banned Find all posts View Profile Close fido666]

I have BFG 265/65/18's on the 150 Kakadu, not sure what I should be running them at. I had Bridgestone Dueler D694 LT's on the old 90 VX and was running those at 38PSI on the black stuff.

[Hutch Addicted PP Member Find all posts View Profile Close Hutch]

Yep 36-38, any higher than that is two rough.


Hutch- 2012 Prado 150, some TJM Kit.

[Whitey1 Advanced Member Find all posts View Profile Close Whitey1]

BFGoodrich AT 34psi all round loaded up with a camper trailer.

[matt150 Avid PP Poster! Find all posts View Profile Close matt150]

Pushed my LT AT3 Coopers up too 40psi cold. Seem to handle better, shall see how they go.

[butane8 Avid PP Poster! Find all posts View Profile Close butane8]

to answer this question, look at your tyres .... look at the scruff marks boys.... that will tell you not other members ..

tyre pressures are visbile on the outside.. cheers butane , just food for thought...

[mrkrinkle Senior Member Find all posts View Profile Close mrkrinkle]

I've been running my ST Max at ~36 however I only seem to get around 2psi raise once warm.

Think I need to drop a few psi and see how that goes?

[krypto Avid PP Poster! Find all posts View Profile Close krypto]

I recently experimented while towing and driving up north. Pressure rise is a direct indicator of temperature rise and how hard the tyre is working.

With a fully loaded car and camper (1600kg) my rear tyres were going from 50 cold to 60 plus hot. Raising the pressure to 54 kept the rise to 59 so obviously the rear tyres were doing a lot of work. The fronts were going from 45 cold to 48 hot.

On corrugations when loaded with tyres cold F30 and R40 both tyres were getting very hot with the rears rising over 15psi.

When not loaded 28 front and rear worked well on corrugations.

Bottom line is it really depends on driving condition and load, but under inflation will cause serious tyre heating with resulting wear and reliability issues.

Around town I run 38-40 front and rear.

Ultimately it's all a personal choice.

[Whitey1 Advanced Member Find all posts View Profile Close Whitey1]

Holy crap! 50 psi? Never heard of anyone running that sort of pressure except trucks. Have many blow outs?

[AJ120 Out of control poster! Find all posts View Profile Close AJ120]

I recently experimented while towing and driving up north. Pressure rise is a direct indicator of temperature rise and how hard the tyre is working.

With a fully loaded car and camper (1600kg) my rear tyres were going from 50 cold to 60 plus hot. Raising the pressure to 54 kept the rise to 59 so obviously the rear tyres were doing a lot of work. The fronts were going from 45 cold to 48 hot.

On corrugations when loaded with tyres cold F30 and R40 both tyres were getting very hot with the rears rising over 15psi.

When not loaded 28 front and rear worked well on corrugations.

Bottom line is it really depends on driving condition and load, but under inflation will cause serious tyre heating with resulting wear and reliability issues.

Around town I run 38-40 front and rear.

Ultimately it's all a personal choice.

Those pressures you are running are pretty bloody high, 40psi on corrugations and then having it go up 15PSI

50psi on better roads, holy crap!

Whilst I agree with the fact that temperature will affect pressure, those numbers seem a very long way from what I have experienced. How much damage are you doing to everything else running pressures so high?

Cheers Andrew

[wastegate Member Find all posts View Profile Close wastegate]

Using a Sensatyre monitoring system (valve style sensor) on Cooper ST/C I normally run hot at 44psi on longer tar journeys. Amazing to see how much harder the rears work from cold as well as the temp differences front to rear. Across the rears the passenger side differs again from the drivers side in temp increases. With that info I start cold front=40, LR=37 & RR=38. At a final 44-45psi I usually get an improvement in fuel usage of 1L per 100km which is bonus.

I also have a Tyredog screw in type sensor on a set of Cooper STT's with Second Air pneumatic beadlocks and run 36psi all round on tar and down to 12psi on sand. Been down to as low as 8psi on wet rocks and with lockers front & rear makes an average driver (me) look half handy at the wheel and does wonders for the Prado reputation amongst Patrol and Disco onlookers.

[krypto Avid PP Poster! Find all posts View Profile Close krypto]

Heading up north each year we are pretty heavily loaded with gear and supplies including food and water for a family for 2-3 weeks of camping. I do the trip along with some friends driving a range of cars including Prados and 100 series and we all do pretty much the same thing. On the way up I suspect that my Prado is loaded pretty close to it's limits, as are all the vehicles

Tyre pressure is the amount of gas inside the tyre required to support the load and allow the tyre to keep its shape and do it's job. Under inflation will cause excessive deformation and stress on the tyre, as will over inflation. It is common to adjust tyre pressure for ride comfort but this does not necessarily give you the right pressure for the tyre to do it's job.

Tony, I've noticed that the tyres on the sunny side will sometimes be a few psi higher than the shaded side. I've also noticed this with the wheel bearings on the camper, which I check regularly.

Andrew, some of the guys that I travel with have been doing this trip for up to 20 years and they do a lot of camping every year. There's no history of vehicle damage.

None of us have had a blowout, most of the problems occur once we get to the camp ground, let the tyres down and go driving over rocks etc. BFGs are LT tyres and 50psi is nowhere near their limit. You are far more likely to have a blowout by under-inflating and than over heating a tyre.

Earlier this year I came across an old guy driving a 79 series tray top at the end of the Anne Beadell and who was heading up to the CSR. His vehicle was over 4t fully loaded and he did the Anne Beadell without problems with 50psi in the rear tyres. A tyre at 50 with a 4t load is probably riding the same as a tyre at 30 with a 2t load.

The point is that the tyre pressure depends on load, road and driving. It's something that should be adjusted accordingly. Adjusting for comfort alone will not always give you the best result. It is about really taking the time to match tyre pressures to what the vehicle is doing.