So I opened a case with GM customer support and just got off the phone with someone.

I told them the sticker says Z rated tires and I got W rated tires, what gives. Anyway after asking them about it they told me that the W rated tires are actually better than Z rated tires.

They told me that Z rated tires where good to 149 mph and that W rated are good till 168 mph. So I can't really argue with them if they tell me I got better tires out of the deal. At any rate I figured I will never go 149 let alone 168.


If I read that correctly Z rated tires are rated over 149 MPH but they don't say to what so I would assume that 149 is the max speed, since the don't give a definite max speed.

I have had people told me that Z rated are stickier tires but I have yet to actually find anything authoritave that states that.

 

W and Y ratings are a sub rating of Z, lol it's stupid but most people know what "Z rated" means so they advertise that when it's actually W or Y.

 

Most decent ZR rated tires are ultra high performance tires with treadwear ratings in the 200-300 area which means the compound is softer and stickier.

Some budget ZR tires are rated in the 300+ treadwear category which means the compound is harder and lasts longer equalling less grip.

 

This is too wierd...i just looked up all that stuff the other day. Great minds think alike i guess.

 

Motorcycle tires are the same way with the compounds and honestly I would rather GM gave me a bit harder of a compound so my tires last longer. When I buy my bike tires I get the sport tour version so I get a bit of stick and a bit of longer life..

 

Even at a discount the OE Pirelli's are almost $200 each that is rediculous.

There are only 4 different tires available in the size too. I hope I can at least get 20,000 miles out of mine.

 

To be fair, it is an 18" tire. Those are always expensive. Not to mention its rated 200 AA A with a ZR-W performance rating. It doesn't get much more pricey than that. Get smaller rims if you want cheap tires.

 

I am used to paying for tires on my Camaro SS 275/45/17 BFG G-Force KDW don't even cost me that much.

 

that gm service plan thing they offer is $400 and you get tires for th elifetime of your car. that's the one thing i'm for sure signing up for

 

Through the dealership? You end up paying for the tires. Firstly.. judging from current oil life, I will only have to change my oil every 6K miles. It will cost me $30 to do it myself.. The dealership charges $79.99 plus an additional $27.99 for Mobile one. We're talking over $110 for an oil change. They DO give you every other one free.. but they make you change it every 3K miles.

Then they charge like $420+ for the 30K mile work. I worked it out on paper. If tires last 30K miles, I've already paid for the tires. If they last beyond that, I've paid for them and then some. Dealership work is always a huge ripoff. You never get anything for free.