Odd...

I've run 3 MANN filters in my 300SD (its the main brand of Halsey Import) and have never had such problems. I even railed on one back in the day to see what was inside it (the cotton gin thing) and it still didn't seperate.
Just weird that some do it, some don't...

BTW on the ones I have ran...I am pushing 6-8k on synthetic or 3-4k on standard..