S4 tyre pressures? (255/35-19 tyres)

[Warlord2001c]

Hi all,

Just checked my pressures as I hit first thousand miles in my B8 S4 and was surpirised to find the garage had delivered the car with 48+ psi all round.

Fitted with 255/35 19 dunlops and i know it says 50 psi max but cany believe thisi s right running pressure. Been thinking the car felt skittish when the power was applied and think i can see why now.

I've dropped them to 40 front and 38 rear but this is still well over the label on the door jam that says 36 fromt and 33 rear. Car feels alot better on handling and the power steering feels better at low speed too. Guess it was getting confused with the high pressure making it think it was going fast so it reduced the assistance load making it feel heavy and sluggish.

What does everyone else run?

Cheers

 

[Scotty]

Are you reading the door jam sticker correctly?

I have the same size tyres on my A4 and it's the very bottom reading. This has come up before so I happen to have a picture:

Note : this is not an S4 so it could be different due to weights etc

Audi recommend you run at the pressures for a full load at all times. They say if it's too hard then reduce to the unloaded pressures.

I run 39F 44R.

It sounds like they may have failed to adjust the pressures during the PDI. I think they do set they high to stop the tyres getting flat spots if they're left standing for long periods.

I've got Dunlops? What have you got on ?

 

[Necroscope]

I have a S4 on the 19" 255-35 Dunlops, I run to the door sticker 36F, 33R.Anyone else?

 

[Scotty]

I wonder why the pressure for the S4 is lower than my A4 on the rear? Mine's a quattro avant if that makes any difference.

What pressures so they say for full load?

 

[Warlord2001c]

Hi Scotty,

Here you go, the label from my S4 door:

It's running the Dunlop 255/35 R19.

I think you're right though on the PDI, the car was in the showroom for a week before I bought it so guess they had them pumped to prevent flat spots as you say.

Really glad I spotted it now though, it was the only thing I wasn't totally happy with on the car.

Made it feel dissappointing handling wise but its spot on now so well chuffed .

Cheers

 

[Scotty]

I guess it shows they are all different

It says this on the DVD manual I got with mine. Not sure if yours says the same :

"The tyre pressure must be adjusted according to the load the vehicle is carrying. We recommend adhering to the tyre pressure specifications for a maximum load. The tyre inflation pressures are listed on a sticker on the end face of the driver's door. However, if you prefer an extra-smooth ride and the vehicle is not fully loaded, you can select the tyre pressure for a normal load (no more than three people travelling in the vehicle). However, should you wish to drive with a full load you must increase the tyre pressure to the specified maximum.
Under-inflation or over-inflation will reduce the life of the tyres considerably and also impair the car's handling. Correct inflation pressures are very important, especially at high speeds. The pressures should therefore be checked at least once a month and before starting a journey."

 

[techboy42]

Laughably - my dealer removed my sticker as I had fitted 20" RS4 style wheels on. I have just removed them and fitted 19" and now have got a little confused over the posts above. I am in a 3.0TDi quattro - what would people suggest?

 

[Warlord2001c]

I'm running 40 all round now on y 19". 255/35. Feels good and erforms well dry,wet or slippery as hell,in this snow lol

 

[Just Plain Old]

I run mine at the low end of the scale, (B8 S4) they don't last very long (Pzero rosso) but grip seems about as good as it gets in most conditions......

 

[johnnythepie]

could try this i suppose.and have a laff at the tyre prices that you can link to
Tyre Pressure Lookup » Check Your Tyre Pressures for Car Tyres


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