Apologies for the noob question, but what is normally recommended for engine oil as between BMW 5W-30 oil and Mobil 1 0W-40? I was set on Mobil 1, but I learned BMW took this off of their recommended oil list. I realize this may simply be related to marketing, but thought I would ask the more seasoned ZHP folks. I didn't find a thread on this specific issue, but am still learning the site. Thanks!