All models: engine block differences

[Stephen West <stwest@xxxxxxxxx>]

     Greetings:
     
     from previous postings....
     
     >>I have had MB's for years with the "new to BMW" silicon/alluminum 
     >>blocks/cylinder bores. MB has been using this for over ten years ( 
     >>now found in 96'-forward 740's) .
     
     
     
     >Actually, MB suffered the same fate when they introduced the aluminum 
     >engines. Now they too use steel sleeves The BMW problem arises from 
     >poor gas usage
     >.....
     
     I have a questions regarding the type of engine blocks that are used 
     in the 3, 5, and 7 series.
     
     Do '96 and newer 7 series use steel sleeves or silicon/alluminum?
     What is used for the 3 series ('96 and newer)?
     
     
     >>You can take one of these 96's apart at 200k miles (with proper oil 
     >>changes) and see virtually no wear in the cylinder walls. It's THAT 
     >> good.
      
     If the above is true, can you reasonably expect that type of longevity 
     from the 3 and 5 series as well?
     
     Thanks.

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