could some one tell me what the numbers and such work on BMW's? i alrerady know about the 1st one being the series (3,5,6,7,8 series) but the next 2 and the letters i have no clue. thanks

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198? 300D ???K - Future DD
1989 300TE 285K - traded in '12
1984 300SD 186K - Sold in 08
1978 300SD 330K - Died in 05