I've been noticing the rear suspension of my 2000 528iT Sport slowly loosing its compliance. While driving down the street over minor bumps I don't really notice anything, but when I go over frost heaves on the highway at high speed, the front takes the bump just fine, but the rear suspension gives me a harsh ka-thunk. I raised my concern to the dealer during my last regular service. In July Roundel, Mike Miller addressed a similar issue. I copied Mike's response and provided it to the dealer. The dealer said that they didn't notice anything, and if they wanted me to check whatever it was that Mike had recommended (I now can't find my July Roundel!!), it would cost me about $700 if the part wasn't bad (I have a 10 yr extended warranty), so I declined. A few weeks have passed, and I returned to my dealer. This time I drove with the shop foreman, and he confirmed the ka-thunk. He said he'd research and get back to me, and when he did he said it is the shocks and gave me a replacement cost of $900. Ignoring the price for the moment, I have a hard time believing its the shocks. I experience none of the classic symptoms of worn shocks (lack of control, bouncing, etc.), and after all of my research it seems that these shocks should last longer than my 85,000 miles. Of course, I don't want to replace the shocks if this is not the problem. Any thoughts? Might it really be the shocks, or should I ask the dealer to be checking something else? I believe I have the self-leveling suspension.