I have been reading so much about GC on BITOG that I finally had to try it. Last weekend, I put GC in my 1997 Nissan pickup and it's been great so far. The engine has been running a lot quieter than it did on Mobil 1 5w30. My wife's RX330 is coming up soon for an oil change. I was thinking of using GC rather than Mobil 1 5w30 in it. I searched the used oil analysis section but found no info. Suggestions/opinions?