21 inch wheel tire size thoughts?

[Gently Bentley]

I have a 21 reg 50tdi Vorsprong Allroad. This model is probably the heaviest A6 Avant at roughly 2200 kg. It comes with 21-inch wheels as standard on a 245/40 section tire on a rim of 8.5 J. Originally fitted with a continental sport 6 silent tires which were okay, but they don't last even with normal motorway driving. I'm approaching 12,000 miles and they will be due for a change soon, 90+ % has been at just above regular motorway speed on the M4 M5 or A3O3, nothing too stressful for the tire. When I bought the car last March I was surprised it didn't have 255 section tires, 245 is probably a choice for economy and road noise I suspect to keep the consumption as high as possible. The problem is for me now is there is very little in that tire size available, not just in production but actually available to buy now. They're not the cheapest tire either, there appears to be more 255/35/ 21 section tire choice and I know the rim will take them technically but I'm not sure if they are recommended? I think this is the same issue for the S6 although it does have a different offset. The car has four wheel steering which may be a consideration. If you look at some of the American and even European forums they seem to put massive wheels on the cars but usually previous generations. The C8 Allroad has an ET37 offset the S6 is ET43 on the same size rim. Thoughts, please? PS I have spoken to Audi and they were no help as they only do up to 20 inch tires I was told.

 

[Gjjenna]

I had a 2018 c8 Avant on Pirelli 255 40 20 and they lasted a good 25k, however I do long motorway journeys, I’ve now got the new Vorsprung which has the 21” wheels on 255 35, however these are Bridgestone‘s, it’s too early to comment on the longevity of the tyres but first impressions are how quite they are compared to the Pirelli’s, maybe your rim will take the 255 and, if so, I’d go for the Pirelli, buy direct from Tyreleader or Oponeo and have them fitted yourself, hope this helps

 

[Gently Bentley]

I had a 2018 c8 Avant on Pirelli 255 40 20 and they lasted a good 25k, however I do long motorway journeys, I’ve now got the new Vorsprung which has the 21” wheels on 255 35, however these are Bridgestone‘s, it’s too early to comment on the longevity of the tyres but first impressions are how quite they are compared to the Pirelli’s, maybe your rim will take the 255 and, if so, I’d go for the Pirelli, buy direct from Tyreleader or Oponeo and have them fitted yourself, hope this helps

Thank you for your reply. That’s interesting regarding your stock tire size. Even the S6 has 245/40/21 with just a slightly different offset. The standard Audi wheel seems to be an 8.5 J unless it’s the RS6. That rim will take a 255 profile tire. I’ve heard the Bridgestones are quiet and that is a consideration. There is just so much more choice in the 255 profile. I spoke to the tire guy at West London Audi and he thought getting 12,000 miles out of there continentals was pretty good. These are heavy cars and he did say that he’d seen people struggle to get 10,000 miles out of Bridgestones. It really depends on the driving of course. Us Vorsprong drivers have a weight penalty. I presume you have the four-wheel-drive steering and no issues on 255. I will look up the data for you car to doublecheck the offset.

 

[Gjjenna]

Thank you for your reply. That’s interesting regarding your stock tire size. Even the S6 has 245/40/21 with just a slightly different offset. The standard Audi wheel seems to be an 8.5 J unless it’s the RS6. That rim will take a 255 profile tire. I’ve heard the Bridgestones are quiet and that is a consideration. There is just so much more choice in the 255 profile. I spoke to the tire guy at West London Audi and he thought getting 12,000 miles out of there continentals was pretty good. These are heavy cars and he did say that he’d seen people struggle to get 10,000 miles out of Bridgestones. It really depends on the driving of course. Us Vorsprong drivers have a weight penalty. I presume you have the four-wheel-drive steering and no issues on 255. I will look up the data for you car to doublecheck the offset.

Yes, both had/have 4 wheel drive and steer, Audi advise that you should keep all tyres within 2mm of each other for the Quattro system to perform at its optimum. Easier said then done!