Choice of oil

I like running an oil with Zinc already in the mix, although here lately, I've switched over to Motorcraft semi synthetic 5w20 and self mixed a ZDDP additive. I did that because of the lower viscosity. It's been proven to get the oil to the engine sooner on cold startup and (although splitting hairs) takes less HP from the engine with the lighter viscosity. But, be advised of two things. First, if you decide to use a ZDDP attitive be very attentive to the label. There are some out there......stupid as this sounds that have NO zinc OR phosphorous in them at all. This is the additive I use. I mix it in a bucket with the oil and then dump it in. The second thing to be advised of is, everyone will have a different opinion here. All your engine really cares about is the oil pan being full of something that will WORK.
ZDDP Additive