Yep the VL was using Valvoline XLD in it when I purchased it and the previous owner thought it was special oil compared to what Holden Dealers used out of their 44's. I found that I had oil pressure issues at start up and was advised to change it to Mobil 1 which I did and it solved all the issues instantly. One things for certain and that is Japanese Engines were made to better tolerances and as such worked better with better oils. Ecotecs / Buiks can be used running on any old sludge product in them, but of course I don't. One thing I'm finding is that most people are now recommending higher viscosity oils opposed to lower in a V6 Buik or Ecotec. A 20W 60 is a better product in these engines we're using opposed to a 5W 50 so I'm told.