The geek site Bobistheoilguy has many discussions of Mobil 1.I am not a tribologist but it seems that Mobil 1 has too much detergent(=foaming) to use in the M96 .
Joe Gibbs DT40 is touted as perfect for the M96 but their tech info does not mention specific formulation details to minimize foaming.
Some oils that are specifically formulated to minimize foaming/aeration ,seem(??) suitable for the M96 and are more widely available at retail stores. These are the turbo diesel oils specifically recommended for Ford TD trucks.Ford had a foaming issue and these oils address that. Here is a link to some of those:
PowerStroke
I am not recommending any particular oil ,just sharing what I stumbled across.
There seems to be some confusion about the cause of foaming - over-filling,use of after-market additives etc. Anything we do to minimize foaming seems a good plan for the lifespan of both the AOS and the engine.