What are the OE wheel size?

[AnonTomato4195]

I'm looking for a set of winter tires for my OE 20in trapezoid style wheels. I did some googling and I cant seem to find the exact size of these wheels. Are they 9x20 or 9.5x20?
Also, what tire size will fit on these wheels? TireRack seems to be showing me only tires that are 275/30r20. But I did some researching and it looks like there is some flexibility and options.

[Smac770]

S5 20" is 265/30r20 on 20x9.0 et34.
RS5 20" is 275/30r20 on 20x9.0 et22 or et26, depending on the specific wheel. et26 in your case.

As for viable sizes, whatever tire in 20" that the manufacturer says fits on a 9.0" width. Looking at xxx/30R20 and xxx/35R20 sizes for close to stock diameter (26¼" for S5, 26½" for RS5) that fit on 9.0" rims (just looking at Michelin PS4S to check; you need to verify the same for whatever specific tire you are looking at):

255/30r20 - 26"
265/30r20 - 26¼"
275/30r20 - 26½"
(285/30r20 - min width is 9.5")

225/35r20 - 26¼"
235/35r20 - 26½"
245/35r20 - 26¾"

So assuming the sizes are available in the whatever tire you're looking at, 275/30r20 if it's just going to be cold or thin/packed snow covering. Or 235/35r20 if you'll be on fresh/deep snow/slush.

[AccordingToAlex]

Great info above. Just wanted to add that for snow you should be looking at narrow tire widths as they perform better in said conditions.

[bpd]

Good source to use for factory wheel specs

https://www.wheel-size.com/

[AnonTomato4195]

S5 20" is 265/30r20 on 20x9.0 et34.
RS5 20" is 275/30r20 on 20x9.0 et22 or et26, depending on the specific wheel. et26 in your case.

As for viable sizes, whatever tire in 20" that the manufacturer says fits on a 9.0" width. Looking at xxx/30R20 and xxx/35R20 sizes for close to stock diameter (26¼" for S5, 26½" for RS5) that fit on 9.0" rims (just looking at Michelin PS4S to check; you need to verify the same for whatever specific tire you are looking at):

255/30r20 - 26"
265/30r20 - 26¼"
275/30r20 - 26½"
(285/30r20 - min width is 9.5")

225/35r20 - 26¼"
235/35r20 - 26½"
245/35r20 - 26¾"

So assuming the sizes are available in the whatever tire you're looking at, 275/30r20 if it's just going to be cold or thin/packed snow covering. Or 235/35r20 if you'll be on fresh/deep snow/slush.

Thank you! Super helpful. I'm in the Seattle area and we rarely get snow. Maybe once or twice a year. So I'm not too worried about fresh/deep snow. I will go up to the mountains to snowboard 1-2 times a month in the winter. But I think I should be okay with wider wheels if I drive carefully.

I'm looking at Michelin PA4s in 265/30R20 or 275/30r20. I dont think 10mm will make much of a difference in terms of driving safety. But I did notice that the load index is 94 on the 265 while its 97 on the 275. I don't think that will be too much of a concern either. I looked up the carry capacity and the RS5 gross vehicle weight rating is a few hundred pounds under the carry capacity. Should i be worried about going a size smaller for 265 even with the lower load index?

[AnonTomato4195]

Good source to use for factory wheel specs

https://www.wheel-size.com/

Yeah, I looked there from a google search and I saw the 9x20 sizes. I took those sizes and looked up the tire width charts, they were telling me 265mm width was the maximum for the 9in wheel. But the OE came with 275width for the 9in wheel. This made me question either the charts or the website wheel sizes were wrong. Maybe it was 9.5x20 which does have a max tire width of 275? Decided to ask here to double check.

Also, am I reading incorrect wheel/tire width charts or does audi have super wide tires for the OE wheels? Or is the "maximum tire width" more of a recommendation?

[bpd]

I would think about dedicated wheels for your winter tires. Im Seattle area too and I know what you mean. For my '18 S6 with 20" wheel, I purchased dedicated wheels for winter tires that was minus one inch to 19" wheels which then went to a tire size smaller, can't remember size, but the diameter is the same to keep speedo reading correct. I traded in my S6 for the new S5. From the looks of it, I can probably use my winter set that was for my S6 to the S5 now. The diameters will not be correct, but the speedo error is miniscule. If the wheels you have are a spare set, then yes, you just need to get some tires. If you only have the one set of wheels, it is a hassle to dismount/mount etc.
I think you will have a tough time finding winter tires at the size you are looking except for All season Mich's. You probably have more winter options going to 19's or even 18's if they fit. You will get a higher sidewall and narrower footprint to cut thru snow vs pushing snow. Don't need to buy the best looking wheel for winter use. That way you don't mind if they get curbed up from sliding into something. The snow is not a problem driving, its the ice. We do get ice more than snow.

[Smac770]

I don't think the vehicle in question has been specifically identified yet. A5 2.0T vs S5 3.0T vs RS5 2.9T, and coupe vs sportback vs cabriolet, and model year.

If you want to check the wheel width supported by a specific tire, look to the website for that tire manufacturer. Generic charts are generic.

The stock S5 265/30r20 is 94 Y XL. The stock RS5 275/30r20 is 97 Y XL. Why? Probably because that's what the tire market makes at those sizes. E.g, the only 265/30r20 PS4S is 94 Y XL; the only 275/30r20 PS4S is 97 Y XL, etc.

The curb weight for a MY21 S5 sportback is 3924 lbs. The curb weight for a MY21 RS5 sportback is 4056 lbs. If you're not tracking the car or trying to move the contents of your house in one trip, the 94 XL is probably going to be just fine.

The Audi catalog stock 20" winter for the RS5 is 275/40r20 97 W XL: Pirelli WI 270 Sottoz Series II R01 and Continental WinterContact TS850P. No idea if they are any good as winter tires. The Audi catalog doesn't have any 20" winter listed for the A5/S5.

[bluonyx]

Here's a good site I use for OEM wheels and specs:

https://www.hubcaphaven.com/c/3189/a...eels_rims.html

[VVG]

Great info above. Just wanted to add that for snow you should be looking at narrow tire widths as they perform better in said conditions.

Not really necessary. With the Quattro system, you will just fine with OEM sized winter tires. And for the 90+ % of the time that the roads are clear, even in winter, you won't have to compromise your traction as much. Stick with 275/30/20 on the OEM 20x9" wheels. If you really feel you must go narrower, try 255/35/20. I am assuming this is the RS5 we are discussing since the OP mentioned 9 and 9.5" wheel widths.

[bpd]

Winter tire sizing suggestion

https://www.tirerack.com/upgrade-gar...ter-snow-tires

[VVG]

Winter tire sizing suggestion

https://www.tirerack.com/upgrade-gar...ter-snow-tires

Maybe this is great in theory, but like I said, at least with the Quattro system, you don't need to go to narrower tires unless maybe you live in Northern Alaska and may be driving in really deep snow all the time. Even in winter, the roads are usually clear, and you will be sacrificing traction a lot by going to a winter rubber compound AND a narrower tire. I have lived in New England almost my entire life and have done absolutely fine, even in really heavy snow with stock width winter tires on every car I have ever owned.