The disc caliper, not the drum brake stuff.
When I rebuilt it, I took out the bolt, wire brushed it, cleaned everything with brake cleaner, used a pipe cleaner on all the holes, applies synthetic bearing grease, cleaned the brake shims and applies anti seize to them, put it all back together. Was fine for a few weeks, now after my car was sitting for 6 weeks, I went for a drive and it was seizing up. I had to replace the master and bleed the brakes, they work fine, but sometimes that pad drags.
When I say it is seizing, I mean it does not slide open very well, it actuates just fine, I can compress the piston back in and it locks up the wheel, just does not release well, hence me asking if there is a helper spring back there as well.