Tyre pressure

[scatman1963]

hi I have a mk1 lexus gs 300 sport I am running 245/40/18 rear 275/35/18 tyre pressure is 44 psi all round this is what a nationwide garage also this is my 3rd set of rear tyres this year I have had the camber and toe and tracking all lazered they are still wearing on the inside any ideas it's only me that's in the car in the week and weekends my partner 

[graham8370]

Why are you inflating to 44psi?  recommended is 33.

[KayCee]

wow i bet  44 gives a harsh ride

[scatman1963]

I asked the garage what the pressure should be and that's what they said 44 all round another garage said 33 all round then when I took it to this well know nationwide garage they said 44 all round so bit stuck to what I should be putting in I will try 33 all round today thankyou for your replies

[NemesisUK]

Is it not stated on a label on the driver's B pillar, or possibly the fuel filler flap?

[BachelorDays]

Unless the tyre sizes you are using are original spec, do bear in mind you are using low profile tyres in the front and very low profile tyres at the back. That's one reason why you are being quoted different figures. I'd investigate this angle online before settling on the right pressure.

[DJ Les]

Maybe worth reading this recent thread;

 

[NemesisUK]

4 hours ago, BachelorDays said:

Unless the tyre sizes you are using are original spec, do bear in mind you are using low profile tyres in the front and very low profile tyres at the back. That's one reason why you are being quoted different figures. I'd investigate this angle online before settling on the right pressure.

Tyre pressures are determined by axle weight, so as long as you are using the correct (that is as original) tyre load rating, pressures should be the same irrespective of profile.

Bottom line is never go below the minimum pressures as printed in the handbook but experiment upwards (but below the max inflation pressure as stated on the tyre sidewall) to give the best compromise between wear and ride comfort. Also maintain any front to rear differentials in pressures

[scatman1963]

Hi all well I would use the door pillar pressure but it's not for the sport version neither is the handbook I can only say that the sport version are the correct wheels as I ve looked at photos of other gs 's I believe that they are borbet wheels so I can only assume that the tyres and wheels are correct but another issue I have is wear on the inner rear I have had the hunter laser for camber and toe and front track so they all should be correct unless there is another way of setting them up 

[TigerFish]

On my mk1 Sport, I used to run them at 38.

Having said that, if they were over pressure, they’d be wearing in the middle, so it doesn’t sound like the pressure is the issue. They would probably wear even quicker on the inside edge if you dropped the pressure. I’d get whoever does the geo to adjust away from their settings to compensate the camber.


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[ColinBarber]

44 is probably the maximum the tyres are rated for.

Most owners run them at 32 to 36. No tyre shop/garage will give you the correct pressure, it won't be listed in their database correctly.

As above, get the geometry altered to compensate for the tyre wear. I can only recommend Tony at Wheels in Motion to do this correctly, although he may be able to recommend someone in your area:

https://www.wheels-inmotion.co.uk

He was the person who came up with revised geometry for the IS200 to stop it wearing on the inside, settings that Lexus adopted.

[scatman1963]

Are brilliant thankyou I had it done by a garage that are on the alignment page as well