The oil on the diff is 1 liter lsa90 - which I believe what is used for lsd. .5 liter is gl-5 oil only. So granted that the mobil and this other oil will mix, I have like .5 liter of oil that does need to be have LSD additive. Its the .5 oil that is not lsd compliant. I will relook at ace when I have time, kasi unfortunately true value did not have it as of this time. Gas stations nearby actually offered much poorer advice, use their gear oil for the diff! (which I believe is gl-4, although they don't know that... they say they use for all kinds of things)

I am still trying to see if the problem is diff based. After a few days when I have time to buy the proper oil, I will likely drain again. The car is used by my wife for about 2km per day, so I guess no major damage will occur until I find 2 liters of lsd oil or lsd additive.