Rear brakes squealing

[bowtie-till-i-die]

My rear brakes have this low squeal or whine when I almost come to a stop. It all started after I lowered it. I've checked all bends for any hard bends and I also have steal braided lines. The emergency brakes work fine. It feels like there is not enough pressure in the lines. If I adjust it, or rough up the shoes and drums, or bleed them they are perfect for a day or so then the noise comes back. Is there any way to test the wheel cylinders?? And there is not a leak nor is it low on fluid. What do I do? Any help is greatly appreciated

 

[bowtie-till-i-die]

Anybody?

 

[IOWNJUNK]

Might have warped drums. Or they are too thin. I've seen trucks with bungee cords wrapped around them to make the vibrations stop on a few.

 

[19trax95]

My guess would be you have grooves (how ever small they may be) that go around the drum radially. That's probably what's causing your noise. When drums are cut you put a band around them to soak that up (hence the bungee cord) then they should be finished off by using emery cloth to make the direction of the grooves go in a way other than radially.

 

[bowtie-till-i-die]

Replaced Everything on rear brakes, adjusted several times, bled several times. Still has a squeeling, sounds like a whale. I can adjust and all is fine for about a day.
I'm wondering if a NBS m aster cylinder will remedy this? Any suggestions?