Tyre Pressure

[gsgtsg]

Hi,

I have just had a set of four new tyres on my Discovery 2 year 2000. These are the General Grabber AT2 (255/55 R18) tyres.

Please advise what the tyre pressure should be for the front and back when used on road/moterway?

Thanks.

[jmrivera]

Originally Posted by gsgtsg

Hi,

I have just had a set of four new tyres on my Discovery 2 year 2000. These are the General Grabber AT2 (255/55 R18) tyres.

Please advise what the tyre pressure should be for the front and back when used on road/moterway?

Thanks.

Check the manufacturing sticker located on the driver's door... it is your best baseline advice... then adjust according to what activities you are involved in...

Jonathan

[Disco Mike]

And add 5#'s to it so they last awhile.
Mike

[Rover Kid]

Do as Mike suggested, you may also like the ride, especially the front, with the higher tire pressure.

[p76rangie]

Originally Posted by Disco Mike

And add 5#'s to it so they last awhile.
Mike

They spend millions of dollars designing a tyre to run at a certain pressure and then the advise from this forum is to ignore them.

Higher pressure can shorten the life of the tyre. It also affects the grip and handling that you need the tyre to do for you to be safe on the road.

[mcguckiana]

That said Ian, the recommendation for D2 is to have 28psi at the front and 38 at the back. You couldnt always follow the recommended tyre makers pressures...

Angus

[Rover Kid]

p76rangie, I can't disagree with your observation, but I personally think the front of the truck rides a bit smoother with the extra air...not to mention, considering the weight of these trucks adding a few psi shouldn't create a safety issue especially when LR recommends tyre pressure at roughly half the trye pressure most tyres can hold, which, as Mike typically suggests, increase the air pressure and reduce the wear of the tyre and increase mpg (though slightly).

Plus, if the car/truck mfgs were so perfect in designing and building vehicles, Why are there ever recalls, not just because of the build, but design flaws as well??

I personally keep the rear at spec and run the front @ 35psi, then I like the way it .

[p76rangie]

Originally Posted by Rover Kid

p76rangie, I can't disagree with your observation, but I personally think the front of the truck rides a bit smoother with the extra air...not to mention, considering the weight of these trucks adding a few psi shouldn't create a safety issue especially when LR recommends tyre pressure at roughly half the trye pressure most tyres can hold, which, as Mike typically suggests, increase the air pressure and reduce the wear of the tyre and increase mpg (though slightly).

Plus, if the car/truck mfgs were so perfect in designing and building vehicles, Why are there ever recalls, not just because of the build, but design flaws as well??

I personally keep the rear at spec and run the front @ 35psi, then I like the way it .

The tyre pressures listed by Landrover are only for the tyres that came with the vehicle. Pressures vary between makes and models of tyres.

Particularly as you go wider in tyres, increasing the pressures will wear out the centre of the tyre first. Also the tyre will not sit on the road as it was designed.

As stated in a similar thread, the ONLY way to set tyre pressures properly is by using the Static Load Radius set by the TYRE manufacturer.

[DailyDrivenTJ]

Here is another way to do it.

Chalk test.. It tells you at what pressure you get the best foot print from the tires.

Start..


Getting there...


JFYI

[Rover Kid]

That chalk test sounds worth trying, it confirms what p76rangie said about using the tyre mfg specs but you'll be doing it in real time and you should get the most out of the tyres because you're using the exact weight of vehicle, not estimates. Now I just need some chalk!

[mcguckiana]

Originally Posted by DailyDrivenTJ

Here is another way to do it.

Chalk test.. It tells you at what pressure you get the best foot print from the tires.

Start..


Getting there...


JFYI

Gees...someone needs some kill rust...

[Searcaigh]

I would have thought there are too many variables here to put an exact number on it.

Given that some people have a lot more weight up front (steel bumper, winch etc) or a sh!t load of gear in the back, which will influence the handling and the pressures should be altered accordingly perhaps.

I run all of mine at 37 cold and 40 hot.

[antichrist]

Tire inflation pressure depends entirely, for the most part anyway, on the weight each tire is carrying. You can't go by vehicle mfg spec unless you are using the OEM tires, which I'm guessing most of us don't, once it comes time to get new tires.
The only tire mfg spec I've seen on tires is max pressure, which generally is for when the tire has the mas load on it. I've never seen a weight chart from a tire mfg that says for 'y' weight use 'x' pressure. But to use such a chart, if you had one, would require you to weight each corner. Chalk is easier.
The only reliable way to know you have the correct pressure is the footprint test as shown here, and as I mentioned in another similar thread the other day.
Under-inflation and over-inflation are both safety hazards.

[DailyDrivenTJ]

Originally Posted by mcguckiana

Gees...someone needs some kill rust...

Not my Jeep.

[salty]

35 to 40lb front
40 to 45lb rear
depending on how much you have in the back an whether your running at motorway speeds or not. From what you've said I go with 40 front and 45 rear.