Originally Posted By: MolaKule
AW's- AW's don't have to be made of CC killing ZDDP. Extra AW's such as non-metallic polymer esters are very expensive.
Would a cheap HM oil have them? I have heard of ZDDP compounds that are less problematic, too, as per Valvoline's MaxLife claims. And I know that products like Delvac 1 LE 5w-30 have low phosphorous numbers, but obviously aren't weak in the AW department.
Originally Posted By: MolaKule
Shear stable VII's and shear resistant, high viscosity base stocks can keep bulk viscosities from having to be increased.
True, but an extra couple points on HTHS for an older application doesn't hurt, and that's often been the attraction about HM oils, at least for those of us (i.e. OCD BITOGers) who know about the difference, much less care about it.
Originally Posted By: MolaKule
Extra seal conditioners also raise the price of the formulation.
But, how much extra is there between a "normal" SN/GF-5 oil and an SN/GF-5 HM oil, and, for comparison's sake, perhaps a non-ILSAC HM oil? Of course, that could be a bit of a loaded question, but obviously there are limits as to how much could be used in an SN/GF-5 oil versus something else, or am I mistaken in that? How much wiggle room is there, really? For example, I know that pre-ILSAC MaxLife did a pretty good job with leaks in the old F-150 before the rebuild. I never had the opportunity to try ILSAC rated MaxLife. How would it be expected to compare?
Originally Posted By: MolaKule
Now what was the question?
There are a couple. Is Shell nuts or am I? How many different SN/GF-5 oils does one company have to have on one shelf before it's enough?
And, a little less tongue in cheek, if QSGB is SN/GF-5 and nothing else, isn't an SN/GF-5 (and nothing else) Defy pretty darned close to functionally equivalent? I get a bit annoyed because the price differential is $6 to $10 a jug. It's not huge, of course, but that difference alone killed PU in Canada, since it is treated as functionally equivalent to PP.