Tyres A6 Allroad

[Samsell]

Hi ,

Im sure this has been well covered but Im new to this forum . I have on my 2015 A6 Allroad 255/35/20 tyres and looking to put 255/40/20 on to soften the ride , have hit potholes and bent the rims twice , so hoping to soften the blow next time . Is the 40 okay for 20inch wheels 

Thanks any help is good 

[Magnet]

Hello Richard, 

If you increase the tyre profile, you will increase the overall ‘rolling diameter’ and this will affect gearing etc. - so not recommended. 
The way forward would be to fit smaller diameter wheels ( with then the correctly increased profile tyres).

Kind regards,

Gareth. 

[Samsell]

Thanks  Gareth , Im coming around to thinking the same. Im running 40 psi in the tyres now so maybe dropping them down a bit might soften it up a bit 

 

[Magnet]

They are not XL or even run-flat are they Richard? 
If so, both will have an adverse effect on ride quality. 
40 psi seems high to me, but I dint know. Is that the handbook/sticker recommended pressure? 
Kind regards,

Gareth. 

[a6blacked007]

I have same size tyres on my saloon running 34psi all round.

[Samsell]

Thanks for the advise , my tires are due for replacement hence my search for best bet and size , but will certainly look at lowering the psi down  on my existing ones to 38 to start and work from there down if it feels better 

Appreciate the help now to look for a good replacement tire .

[Magnet]

Hello Richard,

Apologies, but that isn’t the way to go with tyre pressures. There is only one correct procedure and that is to adhere to the pressure stated in the handbook/ label on car. 
Do you know what that recommended pressure is? 
Have you got an answer for us whether your current tyres are XL or not, or run-flat or no? 
Can you come back to us on these points.

Kind regards,

Gareth.

[Samsell]

Hi Gareth ,

My tires which were on the car when I bought a couple of years ago are Laufrenn 255/35Z/R29 97Y.

The attached image of door badge does have 40 as option , but tire pressure isnt there for 35/20 ?

Your help is very appreciated 

Vehicle licence reminder - 4S574_.pdf

[Samsell]

Sorry I posted wrong Badge image correct attached 

 

 

Edited May 3, 2023 by Samsell
image issues

[Samsell]

[Entwood]

I presently run 255/40 R20 at 37psi all round as the car is mainly used to tow the tin-tent, so has a fair bit of tail weight as well as a load of kit in the back, its very stable. The previous owner, who purchased the car new, paid an absolute fortune for the 20" wheels - OK they look good, no dispute there - and I put new tyres on when I bought the car. Those tyres are now reaching time to be replaced, and I'm very seriously considering buying some 18" wheels and running on 235/55 R18 tyres, as I think the ride on 20" wheels on the abysmal roads round here is back breaking - literally!!! The car is a dream to ride in cruising the motorways, but a country road with deep potholes......  not good at all 😞 Trying to work out the relative costs of buying a set of Audi 18" wheels off the Bay, and how much I might get for my 20" ones. There appears to be no to little difference in the actual price of the tyres (Continental SC5).

[Samsell]

Its and shouldnt be a confusing issue . My door badge as image shows all sizes but not the 35/20 , but does show 40/20 Gareth has been very helpfull, but It does seem 20/40 is a recommended size .

My previous A6 Allroad 2013 160kw ran on 255/45/19 I put Cooper CS5 Tires on and it was a very nice ride . My present A6 is the Top of the Line 235kw BTDI model with 20inch so it has a lot more torque , very comfortable on highway and general driving , but hard on rough roads hence my search 

[Magnet]

Hello Richard,

Many thanks for your additional detail. 
It would appear that your current tyres are a lower profile than Audi recommend, and your proposed 255/40 size is what should indeed be fitted. 

Who fitted your current incorrect budget tyres? 

I could be wrong, but I fear that the slight increase in tyre profile from 35 to 40 isn’t going to give you that much improvement in ride quality. 
Changing wheel size to 18 inch and fitting 55 profile would be the better, but obviously far more expensive option. 
If it’s any consolation Richard, you aren’t the first to suffer harsh ride with the ‘fancy looking’ largest wheel option. 
When moving to 40 profile with your 20 inch wheels, make careful enquiries whether those tyres would be XL or not. Audi recommend XL for that profile, but that again makes for a harsher ride. 
Kind regards,

Gareth. 

[Samsell]

Again Thanks Gareth , your help has been fantastic 

The tires were on the car when I bought it so dont know who fitted them .

I have been recommended the pirelli scorpion verde 255/40 r20 101 Y so may well look at these  

The choice is large from budget to over the top , so who knows each tire company pushes their chosen brands

[Magnet]

Many thanks Richard,

I thought they may have been on the car when you bought it. Cheapest option available to the seller at the time! 
 

Scorpion Verde? Not sure if this helps, but a family member has had these on a non-Audi from new, and replaced them with a matching set when the originals needed replacing. The second set has lasted longer than the first - probably due to now doing more motorway mileage, so they come with a recommendation in my experience. The current set ( which will need changing with like for like shortly) are marked M&S - Mud & Snow. I also have a similar set on our non-Audi. 
Good luck with it all.

Kind regards,

Gareth. 

[Samsell]

Many thanks Gareth good to hear re the Pirellis .

If I lived close to you Id buy you a beer but Im in New Zealand so will buy one and drink it for you 

Cheers  Richard 🍺

[Magnet]

You can’t fault that principle Richard - many thanks. 
Glad the forum has been of some help.

Kind regards,

Gareth.