One technical phrase immediately comes to mind here: POOPIE DIAPERS!
If a fraction of 1% of newer Toyota engines (that's the estimate I've heard) develop excessive sludge, then all of these engines somehow collectively become known as "sludge monsters." If some tiny number of BMW engines turn poopie diaper like the one above (please provide evidence if the numbers are higher than this) with 15K oil changes, then this means that BMW oil change recommendations and extended oil changes in general are an abomination???
I won't defend 15K oil changes (I'd personally never go that long, and wouldn't be surprised if doing so could eventually lead to problems), but will say that conclusions should be based on trends, not isolated cases. "Green" drives automotive design to some extent, but marketing and competition plays a much bigger role. Hence, "lifetime" fluids, which are evidently refined by fairies using pixie dust from unicorn horns -- a marketing driven fiction. No need to demonize the Greens for decisions made in the Marketing Dept.
[ December 02, 2004, 07:43 PM: Message edited by: TC ]