My brake vibrate under hard braking. I've changed the pad and resurface the rotor, it's still vibrate. Would it go away if I change the rotor? Is aftermarket 2 piece rotor better than OEM's? How much is the price difference.
I inspect the rotor, it has hairy cracks near the perforated holes.

 

You should never attempt to resurface drilled rotors, it's actually not possible to do it correctly. That technique is meant to extend the life of cast iron rotors on your Mom's Buick, not a hi-performance application like a 997TT. You have to replace worn rotors, and no, aftermarket ones are not 'better' in a street application, only more expensive. The steel rotors on the 997tt are among the biggest brakes Porsche has ever made, they're just fine street or track.

 

Agree completely with TT and per my mechanic it apparently holds true for all German autos. I had the rotors on my Audi A6 turned and they lasted about 2,000 miles before becoming completely useless.

 

Is it necessary to use aftermarket brake fluid, or the OEM is good enough.
Is the aftermarket fluid compatible with seal and brake lines?

 

Oem is fine for street applications. Go to aftermarket for track or racing use - something like Motul 600 which has a higher boiling point. Just make sure it's from a reputable manufacturer and you won't have problems with seals and lines.

 

The OEM fluid is ATE Gold, same as ATE Super Blue which are very good DOT 4 fluids. I run GS610 which is even better in terms of boiling point. But the OP problem sounds like worn or warped rotors not overcooked fluid. Even the best fluid requires fairly frequent change, at least once a season- factory rec is every 2 years.

 

I think u need fresh new rotors, there's not much help by just resurfacing them. Go to Suncoast Porsche Parts, they will take care of you for a reasonable price.

 

u should blame who convinced you in the first place to resurface the rotors !!
i never heard that drilled rotors can be resurfaced !?!?
i know its a big damage .. and OEM Break Fluid is great GL

 

The discs have a minimum thickness. Putting new pads on when the discs are on or below minimum thickness is not recommended.
I'm not sure why you would bother machine discs of this design if you have a braking vibration problem. Check your thinkness first. Fit new discs and if the vibration is still there then check the wheel alignment. That can give you a vibration under braking as well....otherwise the front diff is on the way.

 

I'll change the disc.
Thanks guys for your info!