mojonba

Hello,

I am the owner of a 2017 A3 2.0T Quattro with 19" Tire Package. I am trying to figure out the optimum tire pressures but numbers posted on the driver door sticker nor the manual (they are the same) make much sense, especially when compared to the s3 with 19" wheels as well. What would you guys think is the optimum tire pressures for somebody that drives w/o passengers 90% of the time.

plat27265

Follow what the manual says. For the A3 with 19" wheels, it is 33 psi front and 30 psi rear. It can't get any clearer than that. I am not sure what is causing your confusion.

mojonba

30 psi in 35 series tire does not seem reasonable. Plus, an S3 with the same wheel/tire combo gets a 39/36 recommendation?

morris39

It may not be quite as simple if the object is to minimize wear w/o sacrificing performance. My experience is in general that the recommended pressures are a little high, maybe in the interest of safety, and results in greater centre tread wear relative ot the edges. To see the effect the tire has to be off the car, so it takes one season for me to notice.
In my lightly loaded S3 I use 2-3 psi less than recommended. OTH the dealer always inflates to max shown on the door jamb no matter what instructions are given. In my case that is difference of 10 psi for the rear tires.

plat27265

Your reasoning about 30 psi in a 35-series tire is baseless and does not make sense.

The following quote is taken from the article, 'Why Proper Tire Pressure Matters". You can read the full article here: https://blog.caranddriver.com/tread-...ssure-matters/

There are a lot of things car manufacturers consider when specifying the tire pressures in specific models. In this case, an A3 has a different performance rating compared to an S3. An S3 Owner may subject the car to more rigorous and demanding applications or driving activities that may demand the higher tire pressures even though both cars are physically the same including the engine and drivetrain.

The bottom line is that the manufacturer's engineering team and the tire manufacturer determined that the tire pressures in the manual are the best for your car. How they determine it is based on a lot of other factors that mere mortals may find overwhelming if a white paper about it exists. The information is published in the Owners Manual is gospel according to the Car manufacturer. In this day and age of society being so litigious, I trust that the car manufacturer has done their utmost best to have accurate info in that book. Otherwise, they'll be sued by a lot of car owners for misinformation. And, you know that giant corporations such as the VW Auto Group that owns Audi, VW, Skoda, Seat, Bugatti, who employ real lawyers, will make sure that the information that is shared to their customers are not misleading or something that will bring about litigation.

Be at ease that the tire pressure information in the manual is correct. If something goes wrong with your car or tire due to applying incorrect tire pressures, Audi or the tire manufacturer can decide not honor the warranties because you didn't follow the book. Are you willing to risk losing your car's warranty just because you felt the published tire pressures don't seem to make sense?

morris39

Are confused and gullible synonyms? LOL