Bilstein Struts for 1999 A6 quattro
Curt
Front - BE5-6508-H2
Rear - BE5-6509-HO
I don't know how the 6508-H2 differs from the 6508-HO, if at all. I suspect it's simpy a part number differentiation.
The previous sole spec for this model was the VNE-4577, a twin-tube shock (read: "lame for this appication) for the front only. Apparently, others have been using the 6508 and 6509 for '97-'02 A6 Quattros with no problems.




