Garage Cabinets, Garage Storage, and Garage Organization

Hello

My daughter has a 2000 SLK230 . She has been complaining to me about a slight grinding sound coming from the rear brakes when the brakes are applied . So today I re-did the fronts and took the back drums off and there is at least 80% left on the shoes . No sign of anything out of order there at all . I'm thinking that the shoes are out of adjustment to the point that they arent contacting the drums enough and making that slight dragging sound ?? That sound correct ?

2nd question , are those rear drum brakes auto adjusting or do they need to be manualy adjusted ?

Thanks for any help

Rear brakes are disk same as front. The brake shoes are for the handbrake.

Bazzle