Hi,

I have a 1991 Westfalia.  On a recent road trip my passenger side rear
wheel started making a bit of a noise.  I have a handy tool to tighten
the huge nut so pulled the cotter pin and was able to get about 1/2 of a
turn on the nut.  I figure I put close (if not more) to the 350 foot lbs
of torque, a 2 foot breaker bar with 185 lbs standing on it to torque
it, then a gentle bounce to get the nut to the next spot a cotter pin
would fit in..

That made the noise go away.  I left the hub cap off and checked the hub
for excessive heat periodically (15 min, 30 min, 1 hr, then hourly)  for
the rest of my drive to my destination and all was good.  It never got
warmer than one would expect with braking.

I got to my destination with no further incidents.

On the way home, about 1000 km later, it started making the noise
again.  I was a bit confused as there was no heat build up... but I
figured what the heck & re-checked the torque on the axle nut. It needed
maybe 1/3 of a turn.

*** NOTE *** There is a cotter pin in the nut, so it's not like the nut
backed off.

I am getting ready to tear into the hub, but I'm curious what I might be
expecting to see once I get in there...

There must be something wearing for the nut to need tightening again.
But from my understanding of how the rear bearings are set up, with the
bearing being torqued down onto the sleeve,etc I don't see how it could
loosen.

Thoughts?

Thanks,
Steve Williams