Blower Motor Lubrication?

Ok, pulled it apart cleaned and oiled. Drilled the hole in the nub just because service will be easier next time. Added a .010" shim to the stack to bring endplay down to .005". I looked through my shelf of petroleum products and decided to use 75w synthetic rear end oil. Lots of cussing getting it apart and a 15 minute search for a clip that I heard hit the floor. Just swept it too and the thing ran off under the bench.

Got it put back in and no more squeeking or squalling. But it does have a light baseball card in the spokes sound. This was before I installed it so it isn't hitting anything in the heater box. Fan spins smooth and free. Could it be the brushes bedding back in, as I did clean them up with some sandpaper?