audi s3 tyre pressures

[cd1969]

can anyone make sense of the tyre pressures on my 2010 s3? the sticker on the inside of the drivers door say 42psi fr and 33rr I havnt a problem with this although 42in the front sounds a bit high. All the tyre garages i have spoke to recommend 30psi allround and every web site ive bin on says 30or31 allround, my problem is, why is there such a big difference in pressures 12psi is a lot of pressure to be down on. Are they higher due to the 4wd?

[ernien]

I'm surprised that nobody's come back on that as I have the same dilemma. Checking various web sites and tyre pressure recommendation sites just turns up a variety of different and confusing values and I agree with you.

The sticker on the door pillar of my 2010 s3 suggests (for half load) 42 p.s.i. front and 33 p.s.i. rear.

I've set them at those values and the ride and handling seem fine but it would be reassuring to get a definitive answer.

Ernie.

[Cupramax]

The definite answer is Audi will have tested the car under lots of conditions for thousands of hours to get an overall best figure for the car (which is whats on the label). The tyre garages will likely be saying what they can see in a book which may be wrong or for an older model (or just a guess off the top of their head)...

[plfrench]

Surely you should take the manufacturers advice above that of other sources? I'm confused why you are doubting this. Insurance companies would no doubt take a similar view if incorrect tyre pressures were ever found to be the cause of an accident.

It's probably higher than you'd expect due to the low profile of the tyres and the need to minimise the tyre flex to avoid the rims getting damaged. The suspension will have been set up to work with the tyres running at this pressure, hence the reason Audi put the sticker on the door.

[plfrench]

cd1969 said:

Are they higher due to the 4wd?

In answer to this, they don't appear to be, my 2011 A3 which is FWD and has standard 18" wheels also has 42 psi in the front...

[FamilyDub]

42psi seems really high... even if Audi do say so!

I think you'd be ok with fronts around 37-38psi. It'll make the ride a bit better too.

I run my GTI on 34psi at the front, and VW say 37-38, IIRC.

[Caulkhead]

Run them at the figures given by the manufacturer to avoid the possibility of being accused of under or over inflated tyres in the event of an accident or insurance claim. The manufacturers take great care to get these numbers right.

[Kevin VRs]

It would appear to me that the engine in an S3 weighs more than in an A3, therefore the pressure at the front needs to be higher (combined with the low profile tres).

[Lucas Ayde]

doogz said:

The 2.0T in the S3 is heavier than a 2.0T fitted to an A3?

No, but Quattro adds something like 100kg to the overall weight of the car I think though it wouldn't all be at the front.

[plfrench]

doogz said:

They make A3 Quattro's as well.

It's not because the S3 is heavier.

As I said above, I think the high pressure is more related to the 40 profile tyres that come with the 18" wheels.