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View Full Version : changed brake pads too late, rotor rooted?



myk
07-04-2010, 11:08 AM
I had a little noise on the EF front left wheel, so promptly changed front brake pads. (bought a set back when I did the rear brakes)
The old ones looked fine on the outside, but after removal saw the inner pads had worn more, and on the left side I had metal on the rotor, hence the noise. (Looked up the records, and they have done 80,000km).

So, some newbie questions: Now a good part of the inner rotor surface looks and feels rough, so I suppose it must be machined or replaced. BUT, when I went for a test drive just now, with new pads, the car is braking well and evenly, no shudder etc. Can lock the wheels without too much trouble.
So I wonder, what is the problem? Excess heating on repeated hard braking?
Rapid wear on the pad on the worn rotor side?
Will the braking become uneven as the pad wears unevenly?
Or is the rotor wear superficial, unimportant, and will disappear over time?

And what's the best way to fix the rotor on a falcon? Does a garage just pull off the wheel and machine it in place? Is it OK to just machine the one surface?

Anyway, I have learned not to rely on looking at just the outer pads.

nashy
07-04-2010, 08:33 PM
hi mate,
the problem as you said with just replacing the pads is they will wear unevenly as the rotor will retain those groves you spoke of thus the noise and shudder will eventually return and drive you up the wall.
my advice if the rotors aint to worn you should get them machined cost me about 100 by memory to get them done or if they are gone completely getem replaced as this ensures that the money you forked out for new pads aint wasted.
to answer the other question the mechanics just detach the rotor and machine it down with a lathe until its nice and straight.
hope that helps.

Mini1
07-04-2010, 10:15 PM
If you have the discs machined or replaced, the very least you should do is have the pads resurfaced to get rid of any transferred imperfections. This can be done quite easily in most shops using a stationary finishing belt sander.
The only reason for the uneven wear is, I believe, the use of the inferior cheap and nasty single piston caliper with (not always) sliding guide pins.

jPod
07-04-2010, 11:05 PM
Your rotors can get away with a machining job if there is enough meat. As mini said, you should resurface the pads too if you have used the new ones on the damaged rotors...