Hello, Recently my neighbor also purchased a Silverado. He said the previous owner used 10w40 oil. He went to change the oil and used 5w30. He told me that he has a lifter noise now, but did not before the change. He said it was completely quiet and the prev. owner used that since day 1. would 10w30 do anything? Or would sticking with the 10w40 be ok? Or should he stay with the 5w30?