View Single Post
      09-26-2012, 09:21 AM   #41

Drives: 2011 M3, 2001 M5, etc
Join Date: Nov 2005
Location: Raleigh, NC

iTrader: (1)

Originally Posted by I LOVE MY M3 View Post
This a 2009 M3 with 14,000 miles. Notice from the rear the mains look pretty good. Then notice the front bearing, remember this is the block side. Next set will be the plate side.
What the heck is going on with the S65? Is this the suspected bedplate deflection causing this? Any ideas?

I don't think these main bearing issues are a result of BMW's poor understanding of tribology but instead are a result of potential design issues in the block structure itself (i.e. seeing greater than expected deflection at extreme rpms that disrupts the bearing oil film? It wouldn't take much to make a significant problem rear its head). The natural attack is to blame the bearing/oil film/oil used/etc; however, I'm wondering if a much more significant issue is at the root of these problems...
Current Stable:
2011.5 M3 sedan 6MT, Silverstone, slicktop
2001 M5 LeMans Blue/Silverstone
2006 330i 6MT Red/black, ZSP, Nav, etc
2007 328i wagon Silver/gray