2004 Sienna with Right Rear Brake Noise (Groaning)

I have a groaning noise coming from my right rear brake when applying
significant brake pressure, especially when backing down a steep
incline. The noise is not a grinding noise like you would hear from a
brake pad wear problem.

I have taken the car into two different Toyota dealers without
resolution. The 1st said they couldn't find anything wrong and the
2nd didn't even take it for a test drive but said the problem was due
to rust that develops on the brake pads in a humid environment (I live
near the coast). Both said the Brake system (pads, etc) were OK. The
2nd supposedly cleaned off the rust but the problem is still there.

The closest dealer is about 1 hour drive so it's a real pain to keep
taking it back for a song & dance answer.

Has anyone else seen or have a fix for this problem?

oldt wrote:
> I have a groaning noise coming from my right rear brake when applying
> significant brake pressure, especially when backing down a steep
> incline. The noise is not a grinding noise like you would hear from a
> brake pad wear problem.
>
> I have taken the car into two different Toyota dealers without
> resolution. The 1st said they couldn't find anything wrong and the
> 2nd didn't even take it for a test drive but said the problem was due
> to rust that develops on the brake pads in a humid environment (I live
> near the coast). Both said the Brake system (pads, etc) were OK. The
> 2nd supposedly cleaned off the rust but the problem is still there.
>
> The closest dealer is about 1 hour drive so it's a real pain to keep
> taking it back for a song & dance answer.
>
> Has anyone else seen or have a fix for this problem?

You did not mention what trim package it was but, are you sure that it
has disk brakes and not drums on the rear? What condition is the brake
fluid in? It should be clear with a slightly yellowish color.

Some things to check.

If it has disks, I would check for the fit of the pads on the calipers,
making certain that they fit tight.

Look at the surface condition of that rotor, make sure it's not grooved
or worn to have any reason to induce a "chatter".

Bleed the rear calipers, make sure no air is present and no external leaks.

If you have drum brakes, you could lubricate the shoe pivot points,
clean out any brake dust and rust with compressed air (wear a mask), and
then adjust them. Make sure that the springs that hold the shoe to the
backing plate (they look like coil springs with a pin through them) are
not broken or missing. Clean braking surfaces with brake cleaner.

Make sure that the emergency brake system is adjusted and working
correctly if either disks (remove rotor to check if internal shoes) or
drums.