I recently read about this in an old Star article but the covered model years were not addressed. Which model years are covered as far as this being a routine maintenance item?

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2008 GL320CDI 6K
1970 280SL 112K
1982 240D 210K (Sold)
1973 220D 220K (Sold)
1967 200D 160K (Sold)
1992 400E 139K (Sold)
1988 300E 148K (Sold)
1987 300D 257K (Sold)
1991 300E 108K (Sold)
1987 300E 131K (Sold)
1978 300D TMU (Sold)
1980 300D TMU (Sold)
MBCA Member