I think it is important to note, just because in the old days ZDDP was needed in oils to assist wear characteristics, doesn’t mean that it is needed
in todays oils. Oils have improved immensely over the years. Todays knowledge of chemistry and engineering have created oil blends that give us oils
that far exceed the wear characteristics of yesterday’s blends. Todays blends have chemical replacement elements that duplicate the elements of
ZDDP, so there may be only traces or no ZDDP in the oil, yet have extremely high wear characteristics. These oils have been formulated to assist
todays engines in meeting EPA standards. Since most of us are not experts in the wear characteristics of oil, we act on what we know from our past
knowledge and experiences. The past is behind us and while relevant, we need to look at present engineering going into the future. I’ve done as much
as my pea brain will tolerate in researching the best oil for my Cad 500. So far the best I have found is a blog by a guy that calls himself 540Rat.
He has taken the time using engineering techniques to test over 240 different oil blends, and ranked them by their ability to resist wear.
https://540
ratblog.wordpress.com/2013/06/20/motor-oil-wear-test-ranking/
This is a tough read filled with testing, engineering data, a lot of self praise, and a lot of information that we don’t need, but is the best I
have found to help me in my decisions relative to the oils that I am using in my vehicles. While it would be best to read most of the beginning info,
for the meat of the blog, grab the scroll button and scroll about 1/10 of the way down to “WEAR PROTECTION RANKING LIST”. This lists oil in their
ability to resist wear by measuring in psi their ability to keep metals from making contact. It should be noted that while he has tested an number of
them ranked very high on this list that have an aftermarket oil additive, he does NOT endorse the use of oil additives claiming that you really
don’t know what you are doing to the carefully engineered chemical blend when you pour in these additives. So he claims it is best to choose an oil
that ranks high on the list straight out of the bottle.
The Wear Protection reference categories are:
* Over 120,000 psi = FANTASTIC wear protection
* 105,000 to 120,000 psi = INCREDIBLE wear protection
* 90,000 to 105,000 psi = OUTSTANDING wear protection
* 75,000 to 90,000 psi = GOOD wear protection
* 60,000 to 75,000 psi = MODERATE wear protection
* 50,000 to 60,000 psi = UNDESIRABLE LOW wear protection
* Below 50,000 psi = CAUTION – EXTREMELY LOW wear protection
The HIGHER the psi value, the BETTER the Wear Protection.
I personally use # 5 5W30 Quaker State Ultimate Durability, dexos 1 – Gen 2, API SN “Plus”, synthetic (green bottle) = 133,125 psi, in my
automobiles and #8 0W40 Mobil 1 “FS” European Car Formula, ACEA A3/B3, A3/B4, API SN, synthetic = 127,221 psi., in my motorhome.
Yes, the Amsoil products right out of the bottle have tested higher on this list, but the cost/benefit ain’t worth it for me.
If you want to see where the oil you have been using ranks, do a command F or Control F, type in the brand of oil, and hit CR to advance through the
article until you find it. Some of the oils that have been the staple of the GMC community for years are surprisingly low on the wear protection
list.
Sooooo….judge for yourself. Choose wisely by making informed choices.
JMHO
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.