I posted this in the general forum before I realized that there's a tech section. I'm posting here and will delete my original post.

I'm in the middle of installing Bilstein HD's on my 02 A6 (2.7T), Quattro, manual.

The OEM strut washer has a smaller outer diameter than the Bilstein supplied one. I used the Bilstein and I'm starting to think I should not have. For reference, see image below from Frank Sheperson's writeup on Audiworld:



This image shows the OEM washer sitting inside of the lower mount/upper spring perch. Because of it's larger OD, the Bilstein washer sits between the upper mount and the lower mount/upper spring perch. As I sit here and think about it, it's probably preventing the upper mount from seating correctly against the lower mount/upper spring perch.

What does everyone else do?

Additionally - should all of the threads on the strut shaft (or strut piston) be used? I noticed that not all of mine are which makes me wonder if I should re-compress the spring and try to torque the nut down further on the strut piston.

Finally - I used an impact to torque these nuts down. I don't have the special socket with the window and didn't think much of using the impact at the time. Now that I'm online, I've been reading some bad things about using an impact for this. Thoughts? There was a small amount of movement in the piston but it wasn't spinning around in the housing.

Thanks,
Ian