How to identify the correct tyre pressure if not exactly match

[deathgod86]

Hi,

I always have question on how to correctly identified my bimmer's tyre pressure.
From the chart, it does not have any exact match.
Thanks in advance for the helps...

My front tyre is
245 / 40 ZR 18 97 Y

and my rear tyre is
275 / 35 ZR 18 99 Y

This is the tyre label at the door

 

[gendong]

my guess is ur tires are a lil bit off compared to the recommended size, as those sizes are for 19" rims...... nonetheless, depending on ur driving style, i'd say anywhere between 32psi to 38psi max?

97Y & 99Y are load index & speed ratings.

 

[goks]

As i don't carry load and for ease of memory I just pump 230 front and back. Mine is an 528i M sports with different profiles like u for front and back, 245 front and 275 rear.


Sent from my iPhone using Tapatalk

 

[deathgod86]

Thanks for the response.

I put 36 psi for both tyres.
Reason being Msia bumps are not standardize.
Even if I put 34 psi, will always get the bottom of my car >__<
I hate the sound of the scratch, and it makes me feel pain ...

Btw, forget to mentioned, mine are 520i M Sport, run flat tyre. (Imported from Japan)