a geat long read i will finish later + as always LOVE the factual info on machinery lubrication + that they DISTINGUISH between mineral synthetics + the REAL stuff as well as the better + lesser characteristics! would love to find the graph machinery lubrication showed as to how much more mineral oils thinned with heat + especially the thickening even more so in cold!!! brother in law noted as he added a 5-20 wolfs head oil stored in his truck at temps in the 20's + less was SOOOO thick!! it came from the used "car" lot he usually buys from that sells REALLY used vehicles for lower prices. good for a thrifty person that like me drives little + is RETIRED!!!