they are both the same speed rating Y
they have a different load rating 93 against 97.
if you have 245-40-18's, the 93 will be normal,the 97's will be XL(Extra load)

 

Take a look at the following links:-

http://www.blackcircles.com/general/load-rating

http://www.blackcircles.com/general/speedrating

 

they are both the same speed rating Y
they have a different load rating 93 against 97.
if you have 245-40-18's, the 93 will be normal,the 97's will be XL(Extra load)

Many thanks for the info. I do indeed have 245-40-18's
Obviously one tyre on the rear has been replaced at some point which load rating would have been the original, 93 or 97?
Anyone know what the TTS comes out of the factory with?

 

For whatever reason, Audi seems to use more than one tire manufacturer so what tire is used is a bit of a crap shoot. It seems that the "other side of the pond" typically gets TTS cars fitted with load ratings of 93 for the 18" setup. That said, one of the OE tires is the Mich PS2 which carries a load rating of 97.

I personally wouldnt be concerned with the 2 different load ratings ...

 

For whatever reason, Audi seems to use more than one tire manufacturer so what tire is used is a bit of a crap shoot. It seems that the "other side of the pond" typically gets TTS cars fitted with load ratings of 93 for the 18" setup. That said, one of the OE tires is the Mich PS2 which carries a load rating of 97.

I personally wouldnt be concerned with the 2 different load ratings ...

Would the load rating effect ride quality?, :? I only ask as I've just replaced both front tyres with 97 and the ride feels a lot harder/more crashey. :? Exactly the same tyre/brand as before (Pirelli PZero Rosso).

 

Yes, higher load rating = stiffer side walls.

 

In theory you would think a higher load rating would mean stiffer sidewalls,but it doesn't always work like that.
For example run flat tyres have solid sidewalls,are uncomfortable but can have a low load rating.
So it's more to do with the construction of the whole tyre not just the sidewalls.

 

I'm still on stock tyres as supplied from new and they are 245 40 18 93Y's

 

In theory you would think a higher load rating would mean stiffer sidewalls,but it doesn't always work like that.
For example run flat tyres have solid sidewalls,are uncomfortable but can have a low load rating.
So it's more to do with the construction of the whole tyre not just the sidewalls.

Wouldn't that lower load rating be a result of how the tyre behaves while flat? In other words, because the tyre must be able to withstand running on flat, it cannot cope with a high load at the same time. :?:

 

more than likely yes,I was just using it as an extreme example.
I handle thousands of tyres each week,so I w
just wanted to show that a high load rating will not automatically have a stiffer sidewall.it will depend on the make etc

 

Not able to check ATM, but doesn't the tyre sticker on the door opening give the load rating, as well as the size and speed rating, for each option wheel diameter?

 

Not able to check ATM, but doesn't the tyre sticker on the door opening give the load rating, as well as the size and speed rating, for each option wheel diameter?

Yep, you're absolutely right I've just had a look
Still can't get my head round how bloody hard this new set is though,
definitely feels harder than before! :?

 

I'm still on stock tyres as supplied from new and they are 245 40 18 93Y's

Same here

 

With all this talk of different load ratings,it slowed me down as I was inspecting tyres today.
Every time I had a Mich,Conti Pirelli,Hankook in my hands I was pulling like mad on the sidewalls,lol

 

Actually I've had another closer look at the door sticker and it' 93y NOT 97!
97 is for snow n ice according to the sticker!