Midwestdrifter
Engineer In Residence
The screws are screwed into aluminum. Stainless steel would cause the underlying aluminum to corrode instead of the sacrificial screw. It's much easier for me to replace the screws that is to replace the aluminum brackets. I typically get about 7 years or so before the zinc coating on the screws is exhausted and need to replace them.Why don't you use stainless steel screws?
Also stainless self tapping screws have a tendency to shear off due to their low tensile strength.