Tyre Pressure on-road

[Jazzy78910 Lurker Find all posts View Profile Close Jazzy78910]

Hi all,

I'm new to the world of 4WD ownership and still finding my way through somewhat. Here's my question:

I have a 120 GXL with some decent tyres that state on the walls "max 80 PSI cold"

I've just pushed them to 50PSI (as 80 sounds ridiculous) but wondering if even this is too much?

What is a reasonable PSI for sealed road driving?

Thanks

edit: Tyres are BF Goodrich All Terrain. Unsure of exact model.

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

50 is too high. Try and few and see how it feels, also compare how much they bag front to rear. At the moment im running around 32psi in the rear and around 38psi in the front. Gives about even foot print front to rear and feels good. You'll notice a big difference in a few psi with big tyres.

[vxcruiser08 Senior Member Find all posts View Profile Close vxcruiser08]

I run 31 PSI all round on my Cooper ST Maxx's. Coopers suggested 30 if I really wanted to. It's perfect for on and off road comfort if you need to do a few km's daily on gravel/dirt roads. They are wearing exceptionally well too. I don't know how you bare the comfort at 50 PSI, they will wear quickly in the middle too.

Another good way of checking if the 4 PSI rule. I use it as a rough guide and have found I am using the correct pressures for my daily driving.

Click here for a write up I found which should be helpful!

[brooksy78 Member Find all posts View Profile Close brooksy78]

I just completed some driver sfatey training and they recommended 38 - 42 for a Prado, depending on load (for bitumen).

Their argument was that lower and recommended tyre pressure are a compromise between a soft ride and fuel economy.

In there view tyres operated best on average 4-6 psi above manufacturers specification (as a general rule of thumb). In a Commodore they recommended 42, and they were sponsored by Subaru and for the Subaru's they suggested 40. These were based on safety alone. But the higher you go the less rolling resistance and the more economical. If you go too high then the tyre profile starts getting distorted and you decrease grip on the road, and therefore become unsafe.

I'm running 38.

[Jazzy78910 Lurker Find all posts View Profile Close Jazzy78910]

Thanks for the quick replies blokes,

I've adjusted the front to 38PSI and the rear to 35PSI. I'll see how this rides and try the 4PSI rule mentioned.

Thanks again!

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

There is a sticky thread in the 120 tyre section that has a whole heap of people and what pressures they run in different circumstances. Have a look through it here http://www.pradopoint.com/showthread...ssure-Database and you should get a feel for the range most people operate in.

Also be aware that ambient temperature can have a huge impact on actual tyre pressure. Last time I set my tyres a few weeks ago it was a coolish morning, I just noticed today on a very hot day that before moving that pressures are about 6psi above what I set them at only 2 weeks ago.

Cheers Andrew