Are d electrons ever delocalized in metallic bonding

It has been my understanding that delocalized electrons that participate in metallic bonds come from the highest primary energy level, specifically from the s and p sublevels and that electrons in d orbitals (from one level lower) do not delocalize.


Palladium however, has its $5d^{10}$ electrons IN its highest energy level because it has no 6s electrons, and yet Palladium clearly has electron delocalization. So do d sublevel electrons delocalize in general? In any metal elements? (such as in Palladium). 


