Slack adjuster and S cam slide in and out

Possibly wrong s-cams that are too long. You should check all of the parts to make sure they are correct. You could take out the bushings and that would not affect in and out movement, certainly nowhere like an inch. Only up and down. There are shims that go next to the slack adjuster but that is only to take out a small amount of play.

 

Think your whole brake setup is moving together instead of the shoes staying put. Since the anchor pins seem fine and the shoes themselves are solid, the S-cam bushings are the likely problem.

When those bushings wear out, the S-cam can slide, and the shoes will stick out even after you adjust. What normally keeps everything in place is the anchor pins and the S-cam bushings. Replace the bushings and make sure the cam is tight and your shoes should sit correctly in the drum again.

 

I'm sure Bendix, Meritor, Haldex, etc has some resources on YouTube to explain the how and why. It's pretty simple, and you seeing it is easier than my explaining why.

All of them have pretty easy to reach tech help over the phone if needed.