That company that 'made' that PDF is selling a product. Nothing they say is backed up by much proof... yet they turn around and ask the GM Lube engineer for his proof/tests. I'll let GM's own record stand as testimony of how 'right' they are.
That fact that the PDF tries to dispute that synthtic oil, with the 'wrong'(!?!?!) combination of metals will not break in properly is complete and utter hog wash.
"we also know that the ring and engine block materials in engines of different ages and manufacture have very different break-in requirements"
whaa?!?!? ZDDPlus is trying to sell a product with FUD, and more to the point bull poop. Please inform us, oh seller of ZDDPlus what motor has such 'very different' break in requirements?
ZDDPlus uses the term 'virgin oil'.. hahahahaha what's a virgin oil? Mobile 1 Extended Performance 10W-30 and Valvoline Premium SM 10W-30. Please tell me how these SM rated oils are NOT compatible for older motors? Yet they pass the industry standard ASTM test sequence for wear.
I am not going to refute the other 'claims' in that PDF... but trust me, if you think an API SM rated oil is 'bad' for flat tappet motors then just look at all the vintage/antique cars still running by using it. I have 4 myself, all run fine.
Use what you like.. you don't NEED all those additives, that is my point. The oil in 2014 has the same levels of ZDDP as the oil that came in your motor 30-40 years ago.
