I believe 10 gallons ( as Dale said not sure) is the correct amount. I could only find 5 of Rando 46 HDZ so I did a partial change. I plan on doing a complete change this winter. My 05 uses (3) Nelson 87610A filters. Yes they are in the large black tank.
Wayne & Kathy
05 Alpine 40FDQS #75330 Towing 24' car hauler, 2012 Spyder, 2003 Harley FatBoy