> >> I hit 22,000 miles just last week on my '06 Sonata GLS V6. Today I
> >> was driving around my campus at work getting some coffee with the
[quoted text clipped - 25 lines]
> I am also dying to know if the inside of the rotor is shot. I assume it
> would at least have some nice grooving.

Signature
-Mike-
mmarlowREMOVE@alltel.net
> Don't tell us what you meant to say Mister - we don't care what you
> "meant" to say...
[quoted text clipped - 5 lines]
> all are up here. Clean up the caliper sliders and lube them up. Make
> sure you have nice, free movement of things and put it back together.
Thanks, Mike. I always do clean and lube the pistons when I do a brake
job...is there any other way?? I am going to leave this to Hyundai to fix
since I am under warranty. Maybe I'll get a new set of pads at least outta
the deal.
Eric
Mike Marlow - 27 Apr 2007 20:22 GMT
> > Don't tell us what you meant to say Mister - we don't care what you
> > "meant" to say...
[quoted text clipped - 10 lines]
> since I am under warranty. Maybe I'll get a new set of pads at least outta
> the deal.
Yeah Eric - there is another way. The piston don't require lube - they get
it from the brake fluid. The fixed part of the caliper and the floating
part need to move across each other freely. That's where the bind usually
occurs. Corrosion builds up and the caliper does not move properly. One
pad will remain somewhat pressed against the rotor after you let the brakes
off. That's why I suggest a good cleaning (wire brush) and some never
seize. As well, the ears on the pads are very often a tight fit in the
caliper. Make sure the caliper is clean to receive the ears of the pads and
that the pads fit a bit sloppy in them. Often, this requires grinding off
just a tad of the ear. If you don't, the pads stick in the caliper.
Floating calipers are designed to be a moving system. Anything that binds
in a floating caliper is a problem and will result in premature pad wear.
Very seldom does the piston present itself as a problem. Most times it's
the two halves of the caliper that prove to be the problem.

Signature
-Mike-
mmarlowREMOVE@alltel.net
Mike Marlow - 27 Apr 2007 20:29 GMT
> Yeah Eric - there is another way. The piston don't require lube - they get
> it from the brake fluid. The fixed part of the caliper and the floating
[quoted text clipped - 10 lines]
> Very seldom does the piston present itself as a problem. Most times it's
> the two halves of the caliper that prove to be the problem.
Hey Eric - sometimes the visual is worth thousands of words. The next time
you take a set of disk brakes apart, take a close look at how the caliper
works. You're a smart guy... you'll be able to look at it and figure out
how it should work. There's really nothing magical about it. Pretty much
common sense stuff.

Signature
-Mike-
mmarlowREMOVE@alltel.net
Eric G. - 27 Apr 2007 21:05 GMT
>> Yeah Eric - there is another way. The piston don't require lube -
>> they
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> figure out how it should work. There's really nothing magical about
> it. Pretty much common sense stuff.
Yes, Mike, I do know how the caliper works. I'm just not using the
right terminology here. Mostly from a lack of sleep and some new
medicine the old doc has me on for cholesterol. Seems to be taking a
toll on me for some reason. My son turns 5 next week and my daughter
just turned 1. I figure in about 10 years or so I might get a good
nights sleep again :-)
Anyway, what I clean and lube are the caliper bolt sleeves. You know,
the thingies that typically have a rubber boot over them to keep some of
the crud out. I wouldn't even begin to touch the pistons themselves,
except to push them in a bit with a C-clamp and piece of wood to make
room for the new pads.
On front discs I really DO know what I am doing, even if I am not
writing it correctly. I just think Hyundai should do the work on this
one for me. And since they will give me a loaner car this time, I
really have nothing to lose.
Rear discs, OTOH, have given me a bit of a problem in the
past...especially with the type of piston that THREADS back into the
caliper. It's not brain surgery, but I have found that they are usually
corroded enough to be a real PITA.
Eric
Matt Whiting - 28 Apr 2007 03:07 GMT
>> Don't tell us what you meant to say Mister - we don't care what you
>> "meant" to say...
[quoted text clipped - 13 lines]
> Eric
>
It may be the caliper binding in the mount, not the piston binding in
the caliper. Mike was referring to lubricating the caliper where it
slides in the mount. I haven't had the brakes on my Sonata apart so I
don't know exactly how they are designed, but most disc brakes are made
to "float" in their mount.
Matt
Eric G. - 29 Apr 2007 00:52 GMT
To follow up to my own post, and to add to the statement I made about not
being able to wait for Hyundai, I put the car up on the lift at work today.
I have to report that my pads are fine all around. When you look at the
inside pad in poor lighting, and with my 40-year-old eyes, it can be very
deceiving.
Anyway, I removed both calipers. On the left (drivers side) caliper, there
was tons of crud inside the caliper pin shoes. Likely a result of some
flooding that has happened here a few times over the last two weeks. I
didn't drive through anything deep, but it was likely enough to cause this.
I cleaned and greased the pins on both calipers and the noise I had has
disappeared. It is really strange that the sound was so similar to the
sound that the pad wear strips make. Even the mechanic at work heard it
and told me my pads were probably gone.
Anyway, case closed for now at least. Thanks for everyones opinions and
help.
Eric