I will be interested to see what the new formulation of the 5W-40
synthetic will contain
zinc wise. 1600PPM currently is a lot of
zinc!
I just recently discovered that the
synthetic Rotella T is not a true sythetic but rather a 'highly refined' version of crude or mineral
oil. The process results in a
oil that has the properties of a
synthetic and is considered a synthetic in the U.S. (due some legal action by Mobil and others). Classified a Group III synthetic.
Here is a brief description of the three types of synthetic oils base:
- Polyalphaolefin (PAO) = API (American Petroleum Institute) Group IV base
oil
- Synthetic esters, etc = API Group V base oils (non-PAO synthetics, including diesters, polyolesters, alklylated napthlenes, alkyklated benzenes, etc.)
- Hydrocracked/Hydroisomerized = API Group III base oils. Chevron, Mobil, and other petrochemical companies developed processes involving catalytic conversion of feed stocks under pressure in the presence of hydrogen into high quality mineral lubricating oil. In 2005 production of GTL (Gas-to-liquid) Group III base stocks began. The best of these perform much like polyalphaolefin. Group III base stocks are considered synthetic motor oil in North America