I want to know if someone could help me. My Kenworth's T-800 uses 2 oil filters, one By-pass filter and one Full Flow. I want to change them by long endurance filters and synthetic oil. My question is, Donaldson just have the Full-Flow filter, Can I use the by-pass "regular" filter with Long Endurance Full-FLow filter? Maybe I will need to change the By-pass more often... I don't know.
Hope you can help me with this.

You may try to get an answer at the "Bob is the oil guy" forum. They have an oilfilter section.