[VACList] Tow vehicle rear axle venting?

[John Sellers <sellersj@xxxxxxxxxx>]

We just finished our first 1200 mile trip with our semi-restored 1960
Pacer, including the Region 7 Vintage Rally at Waldo, Wisconsin.  It was
a blast!

I'm happy to say the trip was completely trouble-free.  It was as if
Little Bubble was glad to be back on the road again.

During walk-around inspections on the road I sometimes caught a whiff of
hypoid gear lubricant around the rear of our tow vehicle, a 1994 Chevy
K-1500 pickup truck.  (Incidentally, the truck was grossed out--in
addition to pulling the trailer--but everything was in ratings.  Barely,
anyway.)

When we got where we were going I crawled under the truck and saw that
the differential housing was wet with oil.  I called my local Chevy
dealer and when I described the symptoms he said, "Were you pulling a
trailer?"  When I said I was, he said it was probably just the rear axle
venting, and nothing to worry about.  He said the axle oil level is
topped up cold, and when the axle heats up more than usual--as when
towing--the oil expands and a little leaks out the vent.  He suggested
checking the oil level to be on the safe side, but doubted anything was
wrong.

Anybody else run into this?

Thanks,
John Sellers
WBCCI/VAC #1587
1960 Pacer