A few thoughts about old lubricants and the failures thereof:

Some oils turn into gum because of interactions with metallic
compounds.  Since we lubricate a very wide variety of metal alloys
and combinations, the success of different applications may seem
inconsistent.  The old BSR company, of turntable fame, had one machine
whose platter bearing (die-cast something on cadmium? plated steel)
seized consistently.  The reddish grease they used on the rest of the
turntable was long-lasting and efficient.  But in that particular
bearing, it turned to an adhesive.

Moreover, in that particular bearing, any residue left in the bearing
would tend to infect the replacement lubricant, too.  I condemned
a few different varieties of light grease before I realized this.
I dunno what the chemistry must be.

WD-40 and its friends are likely as stable as any other lubricants.
However, they're also recommended as cleaners as well as lubricants,
and this may be unfortunate if you try to do both simultaneously.

These sprays consist of a light oil that's rendered even lighter by
a volatile carrier.  The solvent in the carrier does an efficient job
of cleaning, for the most part, but unless you get enough of it in to
thoroughly flush the bearing out, there may be enough residue left
after the carrier evaporates to gunk up the works once again.

Even the best oils will vary in viscosity over their lifetime.
Harrison's chronometer was a success mainly because his escapement
used no oil whatever.  Even porpoise-jaw watch/clock oils (developed
over a couple hundred years of experience) gunk up after a while.

Even so, I wonder if those steel music box disks would benefit with
a bit of treatment with a lube containing an EP (extreme pressure)
component.  Molybdenum disulfide is one.  These guys form compounds
with the steel surfaces such that even if the oil components are
squeezed out under pressure, the compounds won't allow the microwelds
that cause severe friction and galling.

Again, just a few thoughts from an old stereo repairman: you people
are the craftsmen.

Mark Kinsler
Lancaster, Ohio USA
http://home.earthlink.net/~mkinsler1

 [ An experienced piano tech told me today that he's seen WD-40,
 [ applied to lubricate the pedal trapwork, crawl up and into the
 [ loud pedal mechanism!  -- Robbie