S3 saloon tyre pressures

Rupert49

Registered User
For the first time since I've had my car (less than 900 miles) I've just been checking the tyre pressures. Having got down on my hands and knees to find the relevant information on the little plaque located on the bottom of the trailing edge of the driver's door (so much more convenient than listing it in the driver's handbook, don't you think?!) I noted that the recommended pressures for 19" 235/35 tyres are 42psi front and 39psi rear, which I thought strange since all four wheels drive.

The recommended tyre pressures on my previous car, a front wheel drive MG ZT with 18" 245/45 Continentals, were 32psi all round - nice and easy to remember! How come the pressures on the S3 are different (front vs back) and so much higher? The cars have around the same kerb weight, the main difference being the rim size and width/profile of the wheels .. is it perhaps precisely because of those very differences? How does a manufacturer determine what pressures to recommend for any particular car?
 

veeeight

I am a very pretty girl
VCDS Map User
Last edited:

steeve

Registered User
More weight on the front, perhaps the effective radii are the same but need differing pressures to achieve this?
 

Don76

Registered User
Not meaning to be pedantic, but XL tyres do not necessarily have reinforced sidewalls.
It simply means it can carry more load than the std version thru increased inflation.

Many tyre companies achieve this by not stiffening the sidewall but by other means.
 

veeeight

I am a very pretty girl
VCDS Map User
I defy you to find a 40 profile XL tyre that doesn't have reinforced sidewalks ;)

But yes, I take your point :)
 
Top