Here's the deal. Took my Cayman S to Porsche for a service and they said that my front tire has a screw in it, so it needs to be replaced. They also said my two back tires need to be replaced. So they want to replace the 3 tires for 1200.

Now I know for a fact I can get tires cheaper. Right now, I have two Goodyear Eagle F1-GS D3's in my garage size 245/45-18. I wanted to know if I could use these. I don't mind stretching the tire a bit if it's going to save me a few hundred. They are sitting in my garage with no car to go on. I bought them for my 03 Skyline and ended up getting new wheels all together.

The service guy at Porsche told me all tires had to match. But why is this? I think it's BS. It's a RWD car, couldn't the two rear tires be different than the two front tires?

Even if I can't use the Goodyear tires, I want to order tires myself because it will still save me 300 or 400 dollars. What tires do you guys recommend. I was searching around Tire Rack and found some options for front and rear (links below). If I'm going to replace 3, I might as well just do all 4.

Compare Tire Search Results

Compare Tire Search Results

Thanks in advance for all of your help!

Service at Porsche just emailed me back and they said...

"The tires are all supposed to be the same brand and model all the way
around the car - of course the size will be different from front to
back."

Still think it's BS.

Here's how I see it . . . your dealer's service department is going to toe the company line. Porsche considers its cars to be very special (don't we all ) to the point where they only recommend tires that their engineers have tested and developed in conjunction with a few choice tire manufacturers. They award these specially developed tires their coveted N- designation, and even recommend that all tires not only be the same type/brand, but same N- designation as well.

This is because they fully expect people will push their cars to the limit, whether on a track, or the Autobahn, and they want to make sure that owners are safe (remember the Ford/Firestone debacle).

That being said, you're an adult, and it's your car, so you could do pretty much whatever you want - however, you shouldn't expect that your Porsche dealer is going to support or encourage putting on anything other than N- tires. I would agree with replacing all 4 at the same time - and Tire Rack is a good place to look. Good Luck.

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You're right! I am an adult. The thing is, I don't really push my card that hard considering I work and live in NYC.

I do remember the Firestone issue. From what I know the Goodyear is a pretty decent tire. But I can still go with TireRack and get better tires, which is what I'll do.

If someone could leave me a tire brand recommendation for my car, that would be great.

Tire Rack Jim is often at this website, and he's been good tire help. If he doesn't respond to this thread soon, go to The Tire Rack - Your performance experts for tires and wheels and request contact with him.

OEM Cayman S tires include the Michelin PS2s (which you probably have now and are very popular), Bridgestones, and Contis. Few others make our oddball rear tire size (265/40/18, rather than 265/35/18), so if you want the OEM rear size, your choices are few. The 265/35/18 size will work, but it will throw off the accuracy of your speedo and odo readings. They also look a little funny (I use Michelin Cups in that size for track and autocross).

Thanks. I'm going to end up getting the PS2's which won't be much more from Porsche. When I told him I wanted to go with TR they discounted it for me.

Front treads must match and should be at the same wear state, else when you brake hard

Front tires and rear tires don't need to be the same. Grip is not the same even if they are the same tires anyway, depending on the size and weight distribution of the car. Handling characteristics may change, but this is not a huge issue.

Left to right, tires do definitely need to be the same though. Otherwise bad things will happen to you.

Also be sure your tires are really worn before someone tells you that they are too worn. This is a common thing I think, for stealerships uhh I mean dealerships to sell you tires too early. I'm not saying you should run them down to the point of being unsafe, but just learn how to tell when a tire is good and when its worn.