Suspension question

[tereed2 at gmail.com (T. Reed)]

Hey guys...

I put some new Pirellis on the 16v last Friday and my last set of tires was
wearing funny so I took it in for an alignment today. I went to a reputable
shop that was recommended by a friend and is known for aligning vehicles
with custom suspension. The car has H&R springs and Bilstein sport inserts
which have been on there for 6 or 7 years, so my memory of the installation
has faded somewhat.

After they put it on the lift and looked at it for a couple minutes, the guy
waved me over and pointed to my struts, saying that I needed new struts in
the front. He grabbed the strut tube and banged it around on the insert,
saying that that looseness was why my tires were wearing unevenly. I didn't
understand what he was saying at first because I thought he was telling me
that something was actually broken on the passenger side only. It turns out
that the nut "cap" that retains the insert in the tube was missing. On both
sides, he said. I was surprised because I was pretty sure I had put those
back on and I didn't see any way that they could just "fall off" since they
were captive on the shock. Nevertheless, he said he didn't want to align it
until that got fixed.

He waived the diagnostic fee and I left. After I got to work I started
thinking about it and now I am remembering that the cap did not fit and that
it was "standard procedure" for installing Bilsteins to leave it out?

If I remember right, the piston diameter of the shock was much larger than
stock, so the cap would not come close to fitting over it. I drew a picture
and concluded that as long as the shock is always under compression, it
doesn't have to be forcibly attached at the bottom. But, isn't it possible
that the shock would not be under compression (say, if the front of the
vehicle was briefly airborne) and thus the insert would slam in to the
bottom of the tube?

What can I do about this (if anything)? Any thoughts?

To me, the looseness he pointed out should have no effect on the alignment.
The wheel bearing assembly is held in place in the horizontal plane by the
ball joint and tie rod, and only in the vertical plane by the strut
assembly. A loose strut assembly could bang around but it shouldn't affect
the alignment, right?

-Toby