Originally Posted By: SonofJoe
Originally Posted By: dustyroads
@ SonofJoe, the FA-4 and CK-4 oils have to pass the same tests. The difference between them is the HTHS. Both have NOACK max of 13%.
FA-4 HTHS is 2.9 - 3.2 (fresh oil) and after KO90 has to be minimum 2.8 HTHS. I recently saw this on Castrol's site. They are renaming their U.S. HDEO's "Vecton" (at least the new formulas).
There's a very slick March 2016 Shell Technical Brochure titled 'Preparing for API CK-4 and FA-4' that you can Google and download as a PDF.
It's sort of interesting but it's also a bit of a yawn. So CK-4 will contain a better oxidation test than the (very dead) Sequence IIIF that was used for CJ-4? Maybe the (soon to be defunct) Sequence IIIG? Wow! Or even maybe the (toothless) Sequence IIIH? Double wow!! Or even...wait for it....a TEOST test? Oh bliss!!! And this GASOLINE test proves exactly what for a diesel oil? Errrr....errrr...is the correct answer sweet naff all??
And look at all those novel chemistries with exciting names like 'B' and 'C' and even 'B+C' and how they give better than spec wear results. Wow! But then you see that the 'Legacy chemistry' (ie the stuff you've been using for the last ten years) also passes the test and you know with absolute certainty that 'B' and 'C' and even 'B+C' have zero chance of ever being used because the 'Legacy chemistry' is a known commodity and is cheap.
But why all this cynicism? What about the better fuel economy? Look at Figure 5. A 10W30 2.9 HTHS CK-4 oil gives 1% fuel economy benefit over a 15W40 3.9 HTHS CJ-4 oil. Gasp! A whole 1 cP reduction and all you get is 1%? Of course I'm dismissing the 4% you get when the truck minus it's trailer is driving at 20 mph (probably down hill with a tail wind) because this isn't what trucks do for 99% of the time. Did we really need all that industry effort for such a measley result?
And 5W30s? Did I miss something or was this just not mentioned? If so, how real is this??
My advice? Keep putting proper PCMO in your gasoline engine. FA-5? Nothing to see here so move along..
Joe, I did look at the PDF you mentioned and looking at the fuel economy part of it you're being a little unfair. The 1% improvement is at "high speed/high load" and in a heavy duty diesel of this time, that means 1400-1700 rpm with your foot to the floor climbing a mountain. Max horsepower is available in that range and is only needed for a minimal amount of time.
Normal cruising is @ 1050-1400 rpm (my truck is mostly @ 1100-1200) and if not climbing a hill, the engine is at low load where Shell shows a possible 4% gain. That is a large percentage of the time. I didn't look too hard at the chart but the question in my mind is what about low rpm/high load? Most of the time, I let the torque pull me up the hills at 975-1250 rpm and rarely go above 1300 rpm in any situation.
I think if an engine can be designed to use the FA-4's lower HTHS and not ruin the bearings, then fine. It gives me a chill to think about chugging up a hill at high torque / low rpm with such a low viscosity but hopefully the designs are correct for the job. Chevron (and them alone, I believe) is saying that FA-4 is ok in my Detroit DD13 but I'm not about to try it.
After all that typing, my only point is that there is a potential for much better than the (measley) 1% improvement you mentioned in your cynical post.
If I should ever purchase another new truck with the approval of using the FA-4, I'd certainly consider using it.
As this thread is in the gasoline forum, I would just say that there are already oils designed for gasoline engines with the same HTHS as the FA-4 HDEO. If you listen/watch the webinar that akela posted, there are about 2 minutes of info (starting at about 31:00) regarding the use of Shell's new CK-4/SN rated 5W30 in gasoline engines.