Since our engines like to eat cams/lifter wear etc...been researching a lot on high ZINC oils....

Most old school porsche guys think the percentage of zinc should be around 11% which our engine design is over 35 years old.

This bad boy has 12%

I am running their 20w50 right now since its 100* here...so far...it has def quiet the engine down from 10w40 Castrol HM (which is a very high 40w)

http://www.conocophillipslubricants....0TDS%20Web.pdf

 

So in your opinion, is it the viscosity or the "vitamins" that quieted it down? Wouldn't the zinc be more of a "reduce wear over long haul" chemical?

 

The additives I think are helping me...this is one robust oil...porsche guys swear by it..but I am sure the little extra weight helped too...like I said Castrol HM 10w40 is on the higher scale..almost a 50w

Yes ZDDP makes your engine wear FAR less than norm over time (which is a plus for us) however the EPA and some other bodies started blaming ZDDP for not allowing cats go 100K+ miles..

 

Here is the product sheets for regular non diesel applications...

I am happy to see that all grades have ZDDP in it...phosporus and zinc is your ZDDP

 

The Valvoline VR1 Racing oil has ZDDP too, and offered in 20-50.

 

Yep you can and they have a good additive package too...might be easier to find for most than Kendall

http://www.valvoline.com/pdf/VR-1%20...otor%20Oil.pdf

 

Everything sounds fine except your idea that a 40 weight oil is almost a 50 weight oil. If it was almost a 50 weight oil, it would be labeled as such.

And yes, I do like Kendall Lubes.

 

Castrol HM 10w40...IS A VERY HIGH 40 weight...its like 45 weight..look up the specs

 

any idea how the Rotella 15w-40 stacks up against those mentioned above.....since a lot of us are using it ?

 

New Rotella T does not have a good amount of Zinc in it due to new diesel regulations and newer engine designs to cope with such changes...Shell wont release specs on the oil either...I do not think...i think they are reduced to passenger car quantities (low low low)

Here is a quick google search I did....Shell Rotella T

Pretty much if you can find it in CI-4 rating than your ok with it but almost all major chains have the new CJ-4

In our old engine design..we need ZDDP