I would take the motor be done with the dealer. You can get an independent shop to do the axles, thrust arms and contol arms for a fraction of what the dealer is asking. Unless you feel like throwing the dealer a $1,500 bonus for helping you get a new engine.

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2014 BMW 328i Xdrive
2011 BMW 335i M-Sport
2008 BMW X5 4.8i Sport
2000 BMW 528i 5sp