My 90 GL was making a strange metal sound the last week or so.  when
starting it up and driving off to work near or below zero, I heard this
sound which seemed to come from the driver's side rear axle.  it was noisy
the better part of the 3 mile drive to work.  When it was 20 degrees that
afternoon, driving home I heard nothing.  Initially I thought it was the
wind flapping my loose fiberglass panel against the body, but it also
happened the next day identical circumstances.  Now that it's above 32
degrees F, there's no noise.  Taking advantage of the warmer temps, I
crawled under there only to find some rotting of the inboard axle boot but
no seepage of CV grease.  Had slightly worse rot on the passenger side
inboard boot and some signs of seepage.   The CV joints have some miles on
them and re packing was in the plan for April, but what gives?  Could water
have migrated to the inner workings and frozen to the point it was
preventing grease from getting to the metal?  I am not an experienced
vanagon driver in real cold weather, so help for the Northern newbie would
be a big plus.

TIA

Max