two diff tire #s at diff stores - will it matter?

[Mazzy21]

I have settled on Continental ExtremeContact DWS tires for my '09 GT.

On Discount Tire and on TireRack the number on the tires is 215/45ZR18.

Sears is running a sale and there the number on these tires is 215/45R18XL 93Y.

I read on TireRAck that the "Z" means the tires are "Z speed rated" though that in itself doesn't mean anything to me ?? I'm wondering if there is any real difference here? A difference that I would notice? So basically one is Z rated and one is Y rated but will that affect anything at all?

[trb]

Every tire in that particular model is a "Z" rated tire per Tire Rack and the Continental Tire website.

http://www.continentaltire.com/www/down ... eet_en.pdf" onclick="window.open(this.href);return false;

The idiots that put together the Sears ad just dropped the "Z" from the tire size.

Good luck on it.

[Mazzy21]

It's my understanding that the tire at Sears isn't a Z rated tire at all. The mechanic at Sears said "it's a Y rated tire". And if that's the case then the tires are different; I just don't know if that difference is of any significance to me/the car?

EDIT: I'm sorry - I see it now. Thank you!!

[Rayven01]

To the average consumer there's no real difference. Z rated tires are rated for "in excess" of 149MPH. Z was the top rating for a long time (because really.. where can you legally go higher than 150 outside of the Autobahn?) but recently they added W and Y to satisfy speed freaks, Y being in excess of 186MPH.

If you get your vibe going over 149MPH I think the tires are the last thing you'll need to worry about!