Has anybody tried thinner oil with their LS engine? Ii see a few magazines running more and more 5w-20 in theirs and it has me wondering. Everybody I hear tells me "thin is in" Certainly if good oil pressure is present with a 20wt oil, it should be easier and less strain on the oiling system as well with even free'ing up some HP. Its probebly all in my head, but i noticed that when I switched to 0w-30 in my 07 2500HD I lost about 3-4PSI at a hot idle. But everything else is fine. Used to be at 40 but its a hair below now. Any thoughts?