Having just checked previous listings under this topic, I have read:
Don't change, ALL oil seals will instantly leak, Never had any problems..., Coke is forever (ie, dissolves slowly, not necessarily in chunks), Flush, Don't flush, Drain as much petro-based oil, and finally (risking a copyright infringement suit from Nike) Just Do It!

After running through this, followed by a short nap, it seems that:
Turbos benefit most (higher temps near exhaust gasses means more coke buildup, but watch oil consumption for the first few thousand miles; change first at 2K and then at 5-6K; and, some mixing (from an incomplete flush/drain) is not a problem. I'm inclined to "just do it" on my 760 - 206K on the chassis, but only 55K on a new engine and turbo. My 940 has 158K, 740 has 116K, but they will be in the spring. The bricks don't leak and use about a quart in 1500-2000, not excessive for a heavy foot and turbo.

I'd welcome any comments, current thoughts, recommendations, etc., both tech and personal experience. Thanks.

Jim Weiss
83 245T, 90 744T/M46, 90 760T, 93 945T, want more . . .