I have seen a 2003 at my Uncle's place go to almost 400K with ZERO maintenance. I'm talking change the oil at 10K or when there is none on the stick, and fixing only what's broke.
Also have a 2006 LBZ with 362K on it, but just bought it, so don't know the history. Runs great, but throws a random code every once in a while and knocks you back to 40mph. Haven't investigated, because it goes from my shop to the farm 3 miles away is about it. $1000 service truck for beating around the lot and jump stating stuff.
We have an 2009 LMM with 338K on it, got injectors at 106K under warranty, brakes at 121K and never another set since LOL. I think a wheel bearing, and some fuel lines under the truck that finally rusted out.
2009 LMM Service truck, 180K, a couple glow plugs, finally got to where it wanted to regen constantly at about 160K so we fixed that.
2011 LML in my service truck, 149K this morning, don't think we've laid a wrench on the engine other than a DEF quality sensor around 85K.
Other than that, we've have about a dozen other we run close to 100K and trade them. I don't think they are as common as the Cummins to see 500K, but they have been way more reliable and durable than anyone thought they would be in 2001 when they came out. I have had better luck out of my Duramax's than I have the 2010 Dodge 6.7L I bought brand new. It took 2 head gaskets to get to 100K miles, but since I did head studs then she's been fine since at about 190K now.
Not tons of miles on any one truck, but across the fleet we have pretty good luck.
Chris