Bob, I use Mobil 1 5W-30.
Ken, I had copied this info, along withg info from Dr. Haas, and some other info, and use all this info to try to make an intelligent choice. Anything you read on the net you have to take with a grain of salt. You have to use your own common sense as to what may be right and what may be wrong. Although this GM engineer doesn't see the need for synthetics for most applications, I still use and believe in them, as you may not be able to measure what is going on at the bearing - journal, metal-metal interface, and
synthetic I believe gives me that extra protection in my grocery getters along with my cobra engine. I still use
synthetic, but use conventional during break-in.
This GM engineer has some good info. He really slams
amsoil though, not that it isn't a good product, but only some of their claims.
When I had posted the info from Dr. Haas, I had asked at the end if anybody wanted me to post additional info, I was mainly referring to the above info that I had posted here.