i almost seem to find myself doing this to every s10 or trailblazer/envoy that comes into the shop. especially after a brake job as the new rotor is thicker so it rubs the crusty ol backing plate. and 98% of the time we give the customer the option to replace them and they never do. i think the only time we ever do is if we are pulling the axle shafts to do seals or something then theres really no labor involved.

 

Unless I have a reason to pull my axle shafts out (leaky seal, etc), the rusty remains are going to stay there lol. I coated them in some rust-stopping paint to preserve what's left at least.