Brake chatter

Toyota 4runner.93.Changed coil springs,brakes and drums on rear. Got bad chatter on rear brakes when I apply above 20 mph. Readjusted and still have chatter. Pads have ripples in the top now. Parking brake is loose. Was before brake replacement and didn't have chatter. Drums are Chinese from Rock Auto. Went in reverse and applied brakes hard to self adjust and still chatter. Petal not spongy. Assume air is out of line. Rebleed? Replace new shoes? Threw away old drums. Both shoes have chatter marks on them. Replaced one brake line I pinched when replacing coil springs with braided steel when I lowered axle. No leaks holds pressure.

 

HI:
Sorry to say, but you have made a poor choice, OEM drums, and shoes are the only way to go.
The Chinese made drums are garbage, and are guaranteed to be out of round.
I have experienced this many times with these.
I have had new customer supplied drums that were so out of round that you could see the ovality with the naked eye.
They are also made with very brittle iron and are prone to cracking, and hot spots.
This is due to the crap that they throw into the melt before casting.
There is zero Q/C on the melt that they use.
Take them to an auto machine shop, and have them trued up.
The shop will cut them back to round on a lathe especially made to true drums.
It will probably cost about $50.00 for both.
Inspect them every 3 months if you use the car a lot.
Art.

 

Thanks Art. That did cross my mind. I'm looking to get the old drums back if possible