I have a question regarding tires for a 2000 Audi A6 2.7T (110k) in the Dallas/North TX area. I was wondering if someone could help me confirm what I am considering regarding the tire sizes. When I bought the car from an Audi dealership, it had Pirelli's with Italia rims and 245/45/17 size. I feel there is a lot of noise with these tires (Pireli AS).

So, I did a tire comparison and realized that 235/45/17 is exactly the same diameter as 215/55/16 (the OEM size) and given the advanced features on the car (awd/abs/etc), it seems like 235/45/17 is the more comparative match to OEM tires than the 245/45/17s that I have on now. Tirerack also suggests this size for this model year (after market).

Now, with 245/45 I have less sidewall (than the OEM) and feel the ride is a little loud - is 235/45/17 going to be much worse? I know and have seen a lot of posts that this size is OEM in later year A6 2.7Ts like the 04s. Perhaps thats a sign? On my 2000 A6, the 17 inch wheels are aftermarket and I am thinking that 235/45 is going to a quieter ride with relatively little difference from 245/45 and yet be as close to OEM as possible with after market 17s. Is that the right way to think about this?

Also, I am thinking about shifting to bridgestone potenze 960 all season - and dumping the Pireli All Seasons simply because of the noise. Any comments?

 

I cant compare the 235 to the 245 because I have not run the 235's on my car. I have the 245 17's on my 01 2.7t with goodyear eagle gt's and my daughter runs the 16 inch tires and wheels on her 02 2.7t and I will say the ride is totally different. Her car is has much less road noise and the ride is much smoother than mine I know there is a performance tradeoff but it just really surprised me at how different the two cars are just because of a tire.

I know part of my issues are caused by the goodyear eagle tires but they were almost new when i got the car so I will wear them out before I switch. But that said like you I get what I feel is way too much road noise and the ride suffers because of the lower sidewall. I swear I could run over a dime and tell whether its heads or tails with these tires.

I agree with you that the additional sidewall should help curb some of these issues and is definetly worth a shot. If you do change up please post some feedback as I am in the same situation and have been debating as to what size and brand of tire to go to as well.

 

I run P235/45-R17 (oem) Pirelli P6 All-season in the winter and P235/40-R18 Continental Extreme Contact on the RS4 rims the rest of the year. I don't notice any significant difference in road noise between the tires. My gut tells me the 18s ride a little more harshly because of the thinner sidewall. I deliberately stayed with the stock tires for the winter because I wanted a "thinner" tire (the 235s are still pretty wide) for cutting through snow. If I had to do it over, I would have purchased 245/40s for summer tires for three reasons: I like the look of the wider tire, they would fill the wheel well a little more, and the wider rubber might do a better job of protecting the rims. Finally, I find turning up the Bose takes care of any tire noise.

 

Thank you for responding. With 235x45, though they are not stock, they seem closer in circumference and diameter to OEM which means there is lesser variation in speed or revs. I am wondering if it would be easier on a car with 110k miles - I mean I don't want to put any more stress on it than is necessary. Heck I may even be expecting lesser problems with control arms and tie rod ends etc.

With the 17s, 235 is going to have a smaller sidewall (less cushion?) and smaller width than 245 but I am thinking there is not much difference there. I expect 235x45 and 245x45 to be almost the same in terms of noise - but better for the car - any thoughts?

That leads me to brands and treads. I am wondering if its just pirelli p6s. I mean I have read reviews that the bridgestone potenzas are much quieter without compromising on performance. Can anyone vouch for that? And any more thoughts on 235 vs 245 for the car / quattro / control arms / wheel balancing etc?

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padog - check back in a few days - I will post some feed back after I decide.

 

often, road noise is less a function of the sidewall profile of the tire and more to do with the tire compound, tread profile and road surface profile.

just sayin'

 

02A6Beau - like you say, in this case, I agree that perhaps road noise may be less a function of the sidewall profile difference (hardly any difference here between 235 or 245/45). I am leaning towards that too, that it is probably more the tire that I need to worry about than the size. I am all at sea for now and looking for suggestions - I am considering Bridgestone potenza 960 AS. Any other recommendations - for a softer ride?



For the sake of the others:

Between, 235x45 or 245x45, I am inclining towards 235x45 for two reasons ignoring the "road noise" factor totally:
1. Circumference match - rev match - diameter match and therefore possibly better performance and ride.
2. Everyone who sells tires including Tirerack n others suggest 235x45 for after market 17s. Even Audi had upgraded the wheels in later 2.7t models and started using 17" 235/45.

 

I ended up getting the 17" Michelin Pilot Sport PS2 235x45. I am not sure if its just in my head but I feel the steering is lighter - just sort of feels like its not as heavy. But I cant tell much of a difference in terms of road noise. The tires are great - seem to be doing what they do.