I'm not sure how to tell but I've heard it mentioned on the boards here how some weights come off as on the thin or thick side of their rating. Like German Castrol 0W-30 is a "thick" 30wt where oil like Mobil 1 5W-30 is on the "thin" side of the spectrum. So where does Ultra 0W-40 stand? I'm only asking because I'm thinking about switching my Tacoma over to it next oil change since we started carrying it at my work. Ultra is extremely difficult to find and even though my truck calls for and currently runs PP 5W-30, I don't think switching to 0W-40 would cause issues being that this same engine calls for 10W-40 and 5W-40 in other countries outside of the US. Any input on this would be greatly appreciated!