There are a lot of variables that you haven't talked about or don't know. If it's a 528, it's definitely not a stock configuration, it might even be someone's crate engine. Valve train, stock or roller? If the previous owner said 10W40 that's great. Zinc or no zinc? Brand? Let us know more specifics and you might get more help.
I run Brad Penn or Rotella 15w40 diesel oil in my 528 Hemi with .050 restrictors. Not stock. I run a dual external pick up, 10 qt dragster pan. Ray Barton rocker system with spray bars and Morose 4 vane vacuum pump.