I drove it today again, to get some planting soil, and the "hard" left
turns were accompanied by a sound more like an empty plastic bottle
rapping on the axle.  Thinking more about it, I realized I forgot a
possibly-key bit of the puzzle in my last post.

A few weeks ago I replaced the oil in my hydropneumatic suspension.
Unfortunately, the manual seems to be missing a page, but I opened the
bleed screw, let everything drain out, then started the motor and let
even more drain out ('til the reservoir was barely empty), filled the
reservoir with clean and let it run, pumping out old oil 'til it was
clear.  Then I ran the "go down" operation into another bucket (instead
of back into the reservoir) so I've got crystal-clear oil running
through the system's veins.

Anyway, realizing that this might be the "cause", I'm wondering, is
there a specific bleed operation I should do on this system?  Just now,
I put the car up on wheel ramps and released the level controller from
the sway bar and operated the car for a couple of up-down cycles.  It
goes up and down pretty fast, but when I let it down I hear a distinct
hissing like there's air going through the lines rather than oil.
However, given the design of the system, I was guessing (hoping) it
would be self-bleeding so I wouldn't really need to mess around with it
anymore.  Operating this system by hand, it kind of sticks; it's not as
smooth as I'd like it to be, but I'm not excited about putting down $350
for a new level controller/distributor unit.

Anyway, I didn't get that same knocking sound when operating the system
by hand but it did definitely "clunk" (although not as loud as what I'm
complaining about) when changing the level controller from "raise" to
"level".

Any ideas?  I'm thinking about taking this job to the dealer, at least
for diagnosis, but not sure how many of their mechanics have been there
for 20+ years and know anything about this system.  ;)

thanks,
-tom!

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