Hello, have the problem that we have to change the brake pads on one of our trailers. The pads no longer sit firmly on the cheeks and rust has formed between the cheek and the covering. The coverings are otherwise still good. Now new coverings come on top, the question now, must the drums also be turned out? The drums still look good, no bars, are only minimally inrun. Axle is a Sauer Wrz 8130. The trailer is not moved so often, therefore possibly also the release the coverings?