[Biturbos4] Ball Joint progress

Keman keman at interwolf.net
Thu May 13 22:53:54 EDT 2004

(yes, I've got some time tonight to actually write some stuff I've been
meaning to)

Not long ago I drilled and tapped my front lower straight arm balljoints and
installed zirk fittings, injecting grease into them. A fellow lister
inspired the idea and I just had to try it. I was going to do it to the
lower curved arms, but was worried about too little material being available
and I didn't have any dead curved arms laying around to practice on to find
the thickest spot.

I've dissected a bunch of failed balljoints to find out what the failure
cause was...

Water intrusion. None of the boots were cracked, it appears to get in around
the tapered stud area. Upon examination, the NEW suspension arms have a
special washer resting on top of the tapered portion that seems to increase
the sealing capability of the boot. Surprise surprise....

The dead arms that creak were 'dry' inside... and you would think that
simply greasing them would solve the problem. Not so, when I cleaned it out
sufficiently it loosened up, the plastic liner had basically crumbled
causing play to develop when the dry grease is removed. So the creakers
become knockers eventually. Once they start making noise, they're probably

The balljoints are definitely not rebuildable... the arm is made around the
joint, with some pressing/forging being done. It's why we throw the bad ones
away as opposed to returning them for a core.

VW Passat arms are much cheaper than ours. You can get all 4 front lower
ones in a kit for about $180 at the dealer. They are identical to the Audi
ones. We'll happily install whatever joint you provide us at the shop, techs
don't care about parts profit.. they just want the labor. :)

Arms can be had individually from an outside parts warehouse, actual TRW
exact replacements... roughly $40 an arm. I can't remember the name of that
place right now but if someone wants it I'll dig it up.

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