I remeber reading on this forum about someone, I don't remember who, who had an oil analysis on a 10,000 mile change said that their soot levels were too high. I think he went back to 6000 mile changes. I also know a couple people who tried 10,000 mile changes on other turbo diesels and their turbos didn't last.

I run 70% to 80% dino oil and 20% to 30% synthetic and do 6000 mile changes.

__________________
green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

http://ecomodder.com/forum/fe-graphs/sig692a.png