Background info: I bought a brake rotor on ebay for $15, and it is made by a company in California called Autospecialty. The good news is that I got a good deal... they retail for $85 apiece. The bad news is that I need another one, and they retail for $85 apiece. No one that I've called in my area carrys them, and I'd rather not spend the time and $ having one special ordered if I can avoid it.

Relevant question: Does it matter if I have two different brands of rotor on the front end of my 245? It seems intuitive to me that you'd want to keep part replacements symetrical, -- but will the car really know the difference?

Philosophical afterthought: Are any two rotors really the same? (Like snowflakes!=) ... They come from potentially different pieces of steel and are turned/machined/balanced seperately. Invert that statement --> Any two high-quality rotors, even from different manufacturers, should conform to application specifications/tolerances such that they theoretically function identically. Basically, parts is parts, right?

Don't worry about it. Ideally you would have two pristine, seemingly identical rotors, but as long they are both new it shouldn't matter...but I guess you'll soon find out for sure.

I'm sure there would be a lot of people to say you should change both exactly the same, and a lot who will say it's not necessary. Personally I wouldn't worry about it. The way I see it is that the proof will be in whether or not it pulls to one direction or not after you replace the first one. If it breaks evenly, then obviously they are fairly well balanced. I've replaced only one rotor before (because it was warped when I got the car), and I had no problems whatsoever.

For what it's worth, I've always just bought brake rotors at Autozone & Pep Boys. They don't cost much more than you paid for yours on Ebay, and you don't have to worry about shipping. Plus if you need a match you know where to find it.

You will transcend imbalances by keeping the pads from the same box and the rotors of similar style. Calipers are girling rebuilds.