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I'd like to sell my 2008 335i before I encounter the expense of replacing the turbos. I know I plan to sell it before it hits the 7 year old mark (for lending purposes of potential buyers). Car has 50,000 miles right now. I did search but couldn't find an easy answer. Could someone just give a general range of when the N54 factory turbos start to go with "average" driving? I have a Procede but don't get the chance to hammer it much. Thanks.