I put GC in my old Nissan truck about two weeks ago. Before it made a bit of engine "noise" at idle, you know valve train and mechanical noises that an 11 year old engine would make. I had been using Havoline SM/GF-4 5w-30 in it (the one with all the moly) and it was noisy and even used some oil in the roughly 2800 mile oci. Well after 500 or so miles on the GC that noise is gone even on cold starts. I was shocked that an 0w oil would do that. Chalk one up for GC in my book.