Thanks for all the replies! I noticed that the CV issue is more prevalent on W123 cars than W210--only threads on 210 relates to front CVs on 4Matic cars. I went out and looked at the CV boots on the diesel and all the rubber components seem to be intact. What should I look for?

That tap tap tap increasing with speed from a stop is only intermittent and usually occurs in 3rd gear (if that means anything??). Thanks!

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1982 300D-T (sold)
1988 300E (sold)
1994 E320 Wagon (sold)
1995 E320
1998 E300D-T
1999 E3204M Wagon
2001 E320
2005 E320 CDI