Hi, I have found this on Bridgestone web:
"Contrary to popular belief, tyre pressure is not determined by the type of tyre or its size but
upon your vehicle's load and driving application i.e. speed"

Is that correct? BCS.I was told by the man from garage that i should have 290 kPa both front and rear. But in the manual is that front should by 230kPa and back 250kPa. So what is correct. I am wearing Hankook 285/35/R22 106W.

Thanks guys

I'm running 250 k Pa (36psi) nitrogen in mine.

I agree the book says 42psi but that sounds excessive and would also rattle your teeth out! RRS gone
Audi SQ5...Gone Audi Q7 S-Line 240 3.0TDI Gone
Audi A6 Allroad Sport 270 3.0TDI

awd man wrote:

I'm running 250 k Pa (36psi) nitrogen in mine.

I agree the book says 42psi but that sounds excessive and would also rattle your teeth out!

NITROGEN

Care to elaborate...............

gilford wrote:

awd man wrote:

I'm running 250 k Pa (36psi) nitrogen in mine.

I agree the book says 42psi but that sounds excessive and would also rattle your teeth out!

NITROGEN

Care to elaborate...............

Not this again.......

Bit of a gimmick really seen as air is 79% nitrogen anyway.............the theory is the air pressure fluctuates less with temperature change due to there being less moisture in 100% nitrogen.....

Unless you have an F1 car you won't notice any difference

I was thinking more along the lines of where would you get it from, I've not seen it in my local Shell garage

gilford wrote:

I was thinking more along the lines of where would you get it from, I've not seen it in my local Shell garage

Yes a bit of a gimmick.. but the lower pressure loss over time compared to normal air sold it to me...(I hate checking tyre pressures)

Kwik Fit now offer a nitrogen filling service.

plus I was told it is less corrosive than normal air but I'm not so sure now...  RRS gone
Audi SQ5...Gone Audi Q7 S-Line 240 3.0TDI Gone
Audi A6 Allroad Sport 270 3.0TDI

So, back to the OP's question..........

36 PSI you say? I'm sure I was told to run 42?

I've heard the number 42 being bounced around also...

The garage told me "use the same pressures as the 20's" which was 32 on my Disco... I've increased to 36 after the alloy failures (to give more side wall stiffness/protection) and the ride is certainly much firmer as a result.

Are you running 42 psi on yours then? RRS gone
Audi SQ5...Gone Audi Q7 S-Line 240 3.0TDI Gone
Audi A6 Allroad Sport 270 3.0TDI

I think so, cant remember what I put in to be honest! The car is in the Dealer at the moment but will check tomorrow

Right now i have exactly what is book saying...but still not sure what should be...i have found couple treads and getting confused now...
1 / Overfinch saying 37psi front 40psi back (what is more compare to manual),
2 / tyre brands like Michelin and Bridgestone saying it's not about tyre size or value of air, but about pressure - it means any size same pressure - doesn't matter how big is your tyre...
3 /And on the third hand i found treads saying add 4PSI extra compare to manual.

Only what I found for sure right is that there must be difference between front and rear bcs. engine is in front...but that's it...

The other question is, handbook manual contains press. for cold tyres...My tyres will heat up enough after 5 min driving...So even if I take pressure of cold tyre and than drive to nearst petrol station with air...they are hot and I can only guess how much air to put

It make sence that the pressure must be same for all sizes...but as I followed this, when tyres are cold they doesn't look there is enough pressure....when I had 290kPa allround car was bumpy...

So now I am not smarter than before...I think i'll do some tests with different tyres pressures and keep the best one...

Keep close to manufacturer's stated pressures as its the law and an offence not to have correctly inflated tyres. Cops will measure them if you're involved in a prang and insurers can wriggle.


- I've forgotten the margin but I thinks it 10% !!

I personaly run 40 psi front and 42 psi back, i noticed car slides abit in wet compare to 36 psi it use to have, but i dnt suffer from teeth ratle as some say...

Now I have 37psi front and 40 back...i think ride is more firm so propably i will go back to pressures from manual what i found as more comfortable