Correct RS3 Tire Pressures?

[B4YM4X]

I'm a bit confused by how Audi is listing the correct tire pressures for our cars. I have a 2019 RS3 and when I look in the manual I see the chart listed below.

Now based on this chart, for most people, we should be running 39/35 regardless of whether we have the staggered setup or the square setup.

However the tire pressure sticker on the side of my car only shows the pressures for up to 174mph. So it shows 44/39.

Also if the stock tires are rated at 91Y and my new tires I got mounted at 93Y. Based on the load index I should be filling them to 2 psi less correct? So I should be at 37/33?

https://static1.1.sqspcdn.com/static...+inflation.pdf

[o1turbo30v]

On my 225/40/19 winters which are also a 93Y I went with 36psi all around, no issues, car drove awesome.

[S3DUDE]

It is a little confusing but I think that if you are the only driver driving it mostly to and from work and not driving at pass 155 mph you would have to air them up at 39 PSI (Front) and 35 PSI Rear.

[B4YM4X]

It is a little confusing but I think that if you are the only driver driving it mostly to and from work and not driving at pass 155 mph you would have to air them up at 39 PSI (Front) and 35 PSI Rear.

I agree with you. Because the manual says to run 39/35 whether you have the 235 square setup or 255 staggered.

Now I just put on 245/35/19 All Seasons on my OEM fine but I’m going to assume I run the same pressures.

The one thing I’m unsure of is whether I need to adjust for my tire being 93Y. The OEM pressures are based on 91Y. If that’s true I should be running 2 psi less at 37/33 to achieve the same load capacity.

I’m going to wait to see if someone who knows more then I do will let me know if I’m wrong or correct.

[B4YM4X]

On my 225/40/19 winters which are also a 93Y I went with 36psi all around, no issues, car drove awesome.

Of course you won’t have any issues but I just like being precise with things. Being an engineer by trade I tend to be like this lol.

But just like most cars need to change brake fluid every two years, adjust your tire pressures through the seasons, or use the proper torque on the lug nuts. This doesn’t happen on most likely a majority of cars.

I’m not sure I would notice running 39/35 vs 36/36 but some engineer at Audi is paid a lot to make sure 39/35 is the correct psi.

[Chaoscreature]

https://www.tirerack.com/tires/tiret....jsp?techid=72

[Potatohead_RS3]

I feel like I'm just retyping the chart

39F/35R for regular loads if the car has 250 km/h speed limiter
44F/39R for heavy load, three or four people plus luggage, or regular load if the car has 280 km/h speed limiter
46F/44R for heavy load and 280 km/h limiter

Front tire size doesn't matter, and of course the limiter doesn't really matter either since we don't have autobahns.

If you are changing tire size to a different load rating you can look at a load chart and match up the same weight capacity and that would be the correct technical pressure. With a tire being 93 load it will probably run a couple psi lower than a tire with 91 capacity to carry the same weight.

Larger tires almost always have larger weight capacity because they simply have more room inside them for more air. So a larger tire at the same volume of air as a smaller tire will have less pressure inside but the same weight carrying capacity.

[B4YM4X]

I feel like I'm just retyping the chart

39F/35R for regular loads if the car has 250 km/h speed limiter
44F/39R for heavy load, three or four people plus luggage, or regular load if the car has 280 km/h speed limiter
46F/44R for heavy load and 280 km/h limiter

Front tire size doesn't matter, and of course the limiter doesn't really matter either since we don't have autobahns.

If you are changing tire size to a different load rating you can look at a load chart and match up the same weight capacity and that would be the correct technical pressure. With a tire being 93 load it will probably run a couple psi lower than a tire with 91 capacity to carry the same weight.

Larger tires almost always have larger weight capacity because they simply have more room inside them for more air. So a larger tire at the same volume of air as a smaller tire will have less pressure inside but the same weight carrying capacity.

Yup I think you're agreeing with how I interpret things should be.

I'm running All Season 245/35/19 but that doesn't matter and I should follow the 39/35 psi. Technically I should be running 37/33 based on my load rating being 93 but I ran it at 39/35 today and it felt fine. Being an all season tire it was still very comfortable and still handled pretty well.

On the drive home the other day the shop had it inflated to 44/39. Maybe even a bit higher. Because again for some reason my sticker on my car only shows this psi. It was still more comfortable than the OEM summers but I had a feeling the psi was pretty high. Verified when I looked at the TPMS sensors on my car on the way home.

Speaking of that are the sensors usually reading about 2 psi too low?

I measure today before going for a drive and my analog pressure gauge showed exactly 39/35 but on the RS3 it shows about 2 psi lower across the board.

[Chaoscreature]

I measure today before going for a drive and my analog pressure gauge showed exactly 39/35 but on the RS3 it shows about 2 psi lower across the board.

How much do you trust your analog gauge? It's not unusual for any gauge to come out of calibration. In the scheme of things having all your tires at the same pressure is more important than having all of them at EXACTLY the right pressure. Tire pressure can vary quite a bit throughout the day, you can see over 6psi difference just from morning to afternoon due to ambient temperature. Also, make sure all your tires are in the shade when you take the temperature.

[B4YM4X]

How much do you trust your analog gauge? It's not unusual for any gauge to come out of calibration. In the scheme of things having all your tires at the same pressure is more important than having all of them at EXACTLY the right pressure. Tire pressure can vary quite a bit throughout the day, you can see over 6psi difference just from morning to afternoon due to ambient temperature. Also, make sure all your tires are in the shade when you take the temperature.

You know I had the analog pressure for a while so maybe I should check it out. Interestingly enough it was off between that and my portable sun joe air compressor too.

And yes I do take my pressures in my garage after the car has been sitting overnight.