ludikraut

Very few cars have adjustable caster. It's much more common to see adjustable camber. The A8 has a multi-link front suspension, which unlike the more common and less expensive MacPhearson Strut design, does not need as much static camber. On my old A4 it seemed like there was a separate mounting point on the subframe that might dial in a little bit of extra camber, but I never monkeyed with it. Not sure if the A8 has a similar provision - I haven't crawled under it yet to check it out. Probably something I'll be doing this winter, though, as I need to start replacing various bushings.

l8r)

BiturboA6

possibly a few other parts up there,but not air suspension.