Sixto - without reference or experience, it is hard for me to know the difference between typical diesel sound and excessive nailing.

The wagon had a little pinging, especially when cold. I took it on a 150 mi trip that I was late (and thereby a little lead footed) to, it ran better (quieter) after.

The sedan seems to have a little more "clatter" sound than the wagon. It's stronger, for sure, wonder if the ALDA has been tweaked. Will have to inspect.

The wagon has a BB in the line to the EGR. Glad you reminded me, I need to do the same to the sedan.

Thanks for the info to all so far.

Nailing is a painful sound like pounding a nail into concrete. It’s rarely rhythmic. Clatter at any volume can be pleasant to the Diesel purist

Sixto
98 E320s sedan and wagon
02 C320 wagon