Thicker Oil and Variable Valve Timing

[demarpaint]

After significant experimentation, as I'm sure you recall, I "settled" on M1 AFE 0w-30 in our old 2002 Expedition due to its excellent cold temperature performance (that vehicle saw -30C several times) and zero consumption on 12,000Km OCI's. That was an engine that was originally spec'd for 5w-30 and then back-spec'd to 5w-20 in later years when Ford went 5w-20 almost universally across the board. I have no idea what the current owner is putting in it, but I did tell him what I had been running.

Not only are there a lot of myths concerning VVT, but there are also plenty concerning cylinder deactivation.

I remember your experiment. You're also a respected member residing in a colder climate than most of us here. If a cold climate was going to impact performance in any way, you would have noticed, and alerted us. Good point on cylinder deactivation!

 

[Zaedock]

The YF Theta II has an intercooler for the turbo but, no such external cooling for the oil.

Our SXL has an oil cooler.

Again, we've never felt a butt difference between grades in either the Optima or my Ford. I have so much PP 10W30 that I bought on close out that I also used it in my daughter's 2.4L Tigershark in her 200. The Multi-air engines have an oddball valve setup and the change in grade made no difference as well. In fact, she had a bit of consumption (common according to the forums) and it now uses no perceptible oil between change intervals.

 

[Sayonara_Sonata]

The move to 0-40 wasn't nearly as intense as when I ran T6 5-40. It was more than noticeable. Ran as a slug for the first couple of hundred miles. At least if not more than the dif in 87 & 93. It suggests to me that the effect on the function of DOHC intake/exhaust hydraulically actuated CVVT would be more pronounced than mere parasitic drag. It has to be one, the other or a varying combination of the twain.

Personally, I feel the restriction of the CVVT would have the most effect on performance when compared directly & proportionately to parasitic drag.

Now, and for a while, I've blended M1 racing oils with 0-40 using 0-16 to adjust viscosity.

Your results may vary from mine. I've no issue.