Posted for Bill Hannahan <wfhannahan@yahoo.com>:

For some extra dampening I serviced my 320 strut with Mobil 1 synthetic gear
oil last summer, I forget the weight, approximately 75-95. So far no problems,
recently flew 2.5 hrs at 20 deg. F. It taxied fine and was a little easier
pushing back into the hanger without a tow bar.

  You might dilute with Mobil 1 15-50 for less viscosity.
 
 BILL HANNAHAN
 WFHANNAHAN@YAHOO.COM