SteveBBay

Tomorrow I'll be changing my own brake pads for the first time. Everything seems simple enough, but I have a question about rotors. How do I tell if I need to replace or resurface them? Is there a decisive test that can be done to determine rotor condition, or is it a subjective call? I have a 2001 a4 1.8t with the a8 upgrade on the fronts. Thanks for any tips.

Hillbilly

there is a minimum thickness that denotes a rotor replacement. Rotors should be turned every time the pads are replaced, as long as they are within spec. Think about it...........the old pads have worn grooves specific to that pad into the rotor. Now you are putting new, unmarked pads on the same grooved rotor. The pads will comform to the old grooves, thus cutting deeper into the rotor, and drastically reducing pad life. Any reputable brake shop should be able to determine the minimum thickness of the rotor, unless you know it(but you don't, why the hell would you?), and mic out the actual thickness of your rotors. IIRC there is +/- .400 allowable tolerence to determine if the rotors are in fact within spec to turn them down.

RKA

The pads will generally wear down the rotors enough that resurfacing generally isn't recommended.

So assuming you've burned through an entire set of pads on these rotors, I'd seriously consider replacing the rotors altogether.

4Driver4

Rotors are cheap too. Turning old rotors can be pricy.

Shard7

I'd recommend getting a new set of rotors for your first change. When you're done, take the old rotors to a shop and see if they're worth turning; if they are, get 'em done and then you'll be all set for your next brake job. If they're toast, then you've lost nothing.

4Driver4

Sounds about right. Expensive compared to new at about $30 each.

ptempel

I got a set of Brembo OEM rotors for the back wheels for $60 a pair. Think it was from ECSTuning. Can't complain about $30 a piece for rotors.

Audi Junkie

Cheap pads + old rotors & DIY = no problem unless they vibrate.

SteveBBay

Thanks guys