Axle nut

[Larry" <rocco16v@netzero.com (Larry)]

Last month, two years after replacing both drive shaft assemblies, the
passenger-side bearing squalls as I'm leaving the house and turning right.
Go home, check the axle nut, can put about 1/8 turn on it.  Noise is gone.
Three weeks later, same noise is back, nut can take another 1/8 turn.
Tighten it, noise gone.

Now, anyone had this happen ('87 16V, daily driver, NOT abused in any way-no
clutch dumps, power shifts, redline runs, etc) to them?   I'm afraid to take
the thing to work!! (20 miles)
  I'm preparing to replace wheel bearings, but am not completely convinced
this will cure it.
Any suggestions?

Larry  sandiego16V