It's all about oil

This chart can get quite confusing if you're not familiar with the terminology. Interesting reading if you have the time. It may make a difference on which oil you choose.

http://www.micapeak.com/info/oiled.html

wow that was fast. You were certainly right about the terminology. I had to keep going back to the top of the article to reread sections to understand the charts.
No nighmares fortunately. The castrol gtx 20w50 (which is what I use) looks pretty good. The Amsoil looks to be the best petro based oil, but i can't see shelling out the money with as many vehicles as I have and as frequently as I change oil. The other thing I see is that the synthetic oils appear to actually be up to the hype.
Thanks for the post.

It appears as though Mobil 1 is the hands down winner across the board. Next change mine is getting Mobil 1 5w30 and a Purolator Pure one filter. I've always been hesitant to use 5w30 because it's so thin. But the 4.3 needs that to get sufficient oil to the lower cylinder walls quickly on cold start up to prevent piston slap.