540 RAT

The Moderator has asked that my oil test write-ups be posted in my Sticky at the top of the page, titled Motor Oil Wear Test and Lab Test Data. If you are interested in seeing this latest write-up, go to page 6, reply number 108 in that sticky.

540 RAT
Member SAE (Society of Automotive Engineers)

73, Dark Blue 454

I read it. Color me unimpresed. We've no idea what methodology you use for your findings other than you used a "tester" to determine that zinc (ZDDP) is a "myth".

I'll instead defer to real scientists (physicists and chemists). For instance, from here:

http://home.physics.wisc.edu/gilbert...cations/90.PDF

...is this:

"Currently, the most important antiwear and
antioxidant additive that is added to engine oils is a class
of molecules called zinc dialkyl dithiophosphates
(ZDDPs) [14]. Antiwear films generated from ZDDPs
are known to protect rubbing surfaces in engines, acting
as sacrificial films when being rubbed that are constantly
regenerated in a rubbing environment [15]. Studies have
shown that the breakdown products of ZDDPs, and not
the ZDDPs itself, provides the antiwear protection
needed to lubricate sliding steel surfaces within a simulated
and actual engine environment [16,17]. Several
studies show that ZDDPs decomposes upon rubbing to
form a protective film (tribofilm or antiwear film),
however thermal decomposition has also been the
accepted major mechanism of the antiwear film formation
[18–20]. It is well known that these films are comprised
of an amorphous polyphosphate glass structure."

And from here:

http://www.pcs-instruments.com/pdf/e...rch_Papers.pdf (see pg 8)

...is this:

"The film formation behaviour of lubricating oils containing zinc dialkyldithiophosphate (ZDDP) additives has been studied in rolling, concentrated contacts using ultra-thin-film interferometry. It has been shown that ZDDPP-containing oils form chemical films which are additional to the elastohydrodynamic (EHD) films produced by the base oil. ZDDP film formation occurs at elevated temperatures and begins in the range of 130°C to 170°C, depending upon the base oil type. The thickness of the films increases with temperature and test time. The ZDDP films formed are typically 5 to 25nm thick and appear to be solid-like surface coatings."

From here:

https://www.stle.org/assets/document...ature_5-05.pdf

...is this:

"ZDDP forms a protective film—a glass—on the
surface of engine components. This zincphosphate
glass, which is rich in zinc at the
surface and then becomes higher in iron as
it nears the metal’s surface, becomes about
10 nanometers thick and somehow self-regulates
to stay at that thickness."

From here:

http://uhv.cheme.cmu.edu/pubs/SurfChemTrib.130.pdf
(starting with pg 10)

is this,..

"Zinc Dialkyldithiophosphate. There are few lubricant additives that have received as much attention in the literature as zinc dialkyldithiophosphate (“ZnDTP”, “ZDTP”, “ZDDP” or “ZDP”). Originally added to lubricating oil as an antioxidant[25], it was rapidly discovered that it also functioned as a highly effective antiwear and extreme-pressure additive, and is an essential ingredient in the vast majority of current lubricant formulations.

...and this:

"...the (ZDDP) film is intergrown with the oxide on the steel, which presumably also enhances mechanical stability[34]. The mechanism also shows that the glass can function as a digestion agent for iron oxides, which are abrasive and would increase wear."

From here:

http://www.apmaths.uwo.ca/~mmuser/Papers/TL05.pdf

Is this:

"Seventy years after their development, zinc di-
alkyldithiophosphates (ZDDPs) remain key anti-wear
(AW) additives in commercial lubricants used in auto-
motive applications [1,2]. This is particularly remark-
able considering that significant efforts have been made
over the last decade to replace ZDDP in engine oils."

Of course the makers of camshafts disagree with you as well,..and we're pretty sure they'd rather not warranty out camshafts; hence these tech bulletins. For instance from here:

http://www.compcams.com/Base/pdf/Fla...chBulletin.pdf

...is this:

"A major factor in the increase of flat tappet camshaft failure is your favorite brand of engine oil. Simply put, today’s engine oil is just not the same as it used to be, thanks to ever tightening environmental regulations. The EPA has done a great job in reducing emissions and the effects of some of the ingredients found in traditional oils; however these changes in the oil have only made life tougher on your flat tappet camshaft. The lubricity of the oil and specifically the reduction of important anti-wear additives such as zinc and phosphorus, which help break-in and overall camshaft life, have been drastically reduced. In terms of oil selection, we recommend oil with the proper level of “ZDDP”, Zinc Dialkyl Dithiosphosphate additive fortification."

...or how about this from Crower Cams (one of the best):

http://www.crower.com/camshaft-installation

...which says (on pg. 6):

"BE AWARE! Flat tappet camshaft failure is a major problem for the fact that your favorite brand of engine oil is not what it used to be,..anti-wear ingrediants such as zinc and phosphorous have been dramatically reduced,.."

Perhaps my response here should be the "sticky"; not Rat-540's garbage-science accepted by the current moderators on this once credible website.

bluedawg

540rat? Rebutle?

Mid-Years Forever!

7t9l82

zinc wins!

lionelhutz

Until I see details of the test methodology any tests results being posted mean ABSOLUTELY NOTHING.

jb78L-82

Is it me or why is this oil test write up a sticky? Everyone has the right to an opinion but until the results have more detail surrounding the numbers why isn't the writeup just another thread discussion?

73, Dark Blue 454

Well put.

And if this site intends to be a place which has a good reputation where expertise is found, I'd suggest to the monitors/moderators, do a better job of determining what's selected as a "sticky" (credible, worthwhile information of benifit to most) vs. garbage that wouldn't get a passing score in the 6th grade.

lionelhutz

There was thread after thread of the same crap so the mods told him to put it all in 1 thread. But why it's a sticky is beyond me. As you said, it's posted as if the results mean much but I haven't seen any details of the tests performed and the results are useless without that detail.

Also,
Film strength testing is not anti-wear additive testing.
A short film strength breakdown test doesn't test the long term effectiveness of additives.

The ZDDP conclusions from these tests are flawed.