This is their newest high zinc product. http://www.amsoil.com/storefront/zrt.aspx
This is what I run in the sister in laws '04 WJ with 4.0 that was the wifes DD since new. http://www.amsoil.com/storefront/amo.aspx
It has over 210K on it. A couple lifters did their ticking thing at 180K. I Replaced the lifters, cam and other, 'while i'm in there' things. The cylinder walls still had the cross hatching in them and all the bearings had considerably little wear.