PhilNotHill

Filled up my tires yesterday. Inside the divers door it says 41 PSI for all four tires. This seemed high so I checked the manual. 41 psi for high performance tires (summer tires) and 36 psi front and 32 psi rear for all weather radials which is what I have.

My other cars are 30-32. Why is the tire pressure in S4 so high?

Thanks

RickFLS4

41 is for summer tire full load. Check manual and normal load on summer tires is something like 39 front and 34 rear. Not sure about all season. Running tire pressure too high will result in wearing out center of tire too quick.

Bobby Kinstle

I've always filled mine to match what the sticker says. There are two values, one for light loads and one for heavy loads. I use the light load since it's usually just me. I'm shocked at how even my tire wear has been, even subjected to significant amount of spirited driving.

DrGP

I've run 39 psi on all my s4s. The side walls on modern tires are so short and narrow that you can pretty much run what you want within reason. If you have the car heavily loaded, inflating the tires to a higher pressure makes sense. Significantly over or under inflating the tires will result in uneven tire wear. Also you generally will get better tread wear with higher pressure. Lower air pressure will give you a more compliant ride.

brooklyn86

I personally run 37psi in the front and 35psi in the rear and find these pressures provide the best car dynamic for my driving style (i.e. spirited, canyon, etc.).

This comes from some trail and error and advice from an Audizine thread. I've tried it on the OEM summer tires and the new Pilot Supersport (PSS) tires I just got and it works great on both.

It's surprising how much tire pressure affects car dynamic. When I did 38psi all around on the PSSs, it didn't feel so good. When I changed it to 37F/35R, accounting for the additional weight of the engine in the front, they felt a LOT better.

equ

I started my s4 on 19's with 41 all around, then went to 39 all around as it felt too high (low load in the car 99% of the time). Even though I liked driving my b8 a4 at 33f/33r on 18's, I found the rear needed more give, so I ended up at 39f/37r. That was good. Now it's colder out and pressures measured at 37/35.5 on a cold morning, still feels good, but I won't let it get below this. In summary, I agree with above poster. If I had 4 people + luggage in the car, I might go to 39 all around.

jyges

that is why

PhilNotHill

OK. Lots of weight on the front....but the rears have the same pressure as the fronts 41 psi.

RickFLS4

Because full load implies full back seat and / or cargo in trunk evening it out. Normal load is not even all around.

brooklyn86

Bingo