The pre-1958 Dana 44s used in Studes had a threaded hole behind the
bearings to allow you to thread in a grease fitting and periodically
lube the bearings.  They were plugged from the factory however as you
were only supposed to hit them every 25K miles or so; I guess they
figured if they left Zerks in them that the oil change places would
hit them every time and eventually push grease past the outer seal and
into the brake drum.  I liked that, made it real easy to grease
(actually easier than repacking the fronts) but they stopped drilling
the hole about 1958ish.  I have a later model limited slip in my '55
now, so next time I have the axle shafts out I may drill and tap those
holes...  I do have the end play set up properly on mine though as the
bearing races are retained by the backing plates; I had to set the end
play when I swapped the axle in anyways (only had one good set of
brakes)

I'm a big fan of periodic bearing repacks, possibly because I used to
drive early watercooled VWs for years, which *required* periodic
repacks of the rear wheel bearings to keep them alive.  Plus I have no
luck but bad, so no sense inviting Murphy over for a visit.

nate