The aluminum is louder somewhat than the plastic stock stuff; but if it's kinda a grating squealing sound; check to make sure the screw that holds the aluminum lock collar onto the outer shaft that rests just below the squash plate isn't carving into the inside of the squash plate underneath. If it is; make sure it's tight or replace with another screw that is shorter. I lubricate the sliding components; well everything in the squash with a thick grease. Lithium or Tri-flow grease. Oil, I think is too light IMO, for bearings, the sliding upper on the squash; try to squeeze some grease into that. Wipe most of the excess off.

Not knowing the noise; it may 'break in' and dissappear; but I don't know. If it's lubricated good, You've done about all I think You can do. If it gets louder, then maybe a faulty part.