I read up a bit on oil from this:
http://www.supramania.com/aehaas/

and learned more than I knew going in. He made a good case for 0W oil, especially for start up even if you don't drive in Nome Alaska. It seems that the start up can cause a bit of wear that the thinner oils combat better than thick (at ambient temps). Synthetic being better than Dino. I understand the battle of the definition of synthetic in CONUS and Europe.

He does recommend Mobil1 0W-30 and that is really the only 0W oil I can find at my price point.

Question: Why not use a 0W oil for start up wear benefits? Seems better than 5W.

 

A quality thinner oil at start up does protect better against wear, on that I think we all agree. The disagreement stems from the fact that I've pointed out that there are 5w oils that are thinner at "real world" temperatures than 0w oils, and therefore I suggest those instead. SpitfireS has made the statement that all 0w oils will always be thinner than 5w oils. When I pointed out that it's simply not true, he then says my examples must not be actual 5w oils then, that they're actually 0w oils in 5w oil clothing.

 

After reading the discussion and summarizing the points made by the two experts, I concluded that as long as you use a quality synthetic oil and change them at a conservative intervals, there isn't much to worry about.

I personally use 5W-30 or 10W-30 synthetics since I am located in LA. So far I have used mobil 1, catrol edge and castrol ti. I add about 1/2x per oil change and car runs fine. I may try penzoil next time. Amsoil is a little more pricey and not readily available which steers me away from it but I heard mostly good things.

 

A thinner oil at a cold start will allow more oil volume being pumped through the cold engine, and yes, that's a good thing IMO.

Based on 2013 data that you did not mention at the start.

Based on my own research I did a couple of years ago, if you call browsing websites to find TDS's research.
This did show the 5W/10W oils were thicker, even around 0C.

At this point providing the oils in question.

Partly based on the data itself, partly based on my interpretation of that data.
Who am I to interpret it anyway..?
I'm NO expert.

 

[/quote]
Based on my own research I did a couple of years ago, if you call browsing websites to find TDS's research.
This did show the 5W/10W oils were thicker, even around 0C.
[quote]
So you are saying "most" 5W oils are, as the label indicates, thicker than 0W oils at ambient (0C 32F) but you have found "some" oils to have quantifiable, demonstrated properties (tested by somebody) that qualify them for 0W oils?

Merlin has identified some 5W oils that have properties at real world (that where I live) of 0W oils.

Is this thing about taking those oils down to -35 or whatever the benchmark is for testing, to see what should be listed as 0W vs 5W oils?

As I don't live in Minnesota, do I need to care?

 

Hmm... no.
Don't forget, this was done around 2008 - the list is older than I remembered.

Looking at this list now, I would say the Amsoil XLF was also pretty close to a 0W.
It's the only one with a V40C below 60 cSt and has a high VI.
All the other 5W's are clearly completely different oils compared to the 2013 5W oils.
(Valvoline maybe too)

It does not matter where you live, you may care about oil anywhere....

The point is, if you want your oil to be as thin as you can get it when the engine is not at operating temp but still be a 30 weight AT operating temp you could, in 2007-2008, buy the syn ~10Cst @ 100C 0W-30 and call it a day.
Nowadays it is not that clear anymore as some oils labelled 5W's have "caught up big time"as Merlin showed.
It looks like the 0W's have not developed (at all) and the oils labelled 5W have.
Maybe SAE should introduce the 2W spec for them?

 

all of this info is making my headspin. i may have to take a month to read up on all of this to fully understand. lol

 

1. Most of the time, but I remember -18 below 0* once years ago (schools had to close b/c couldn't get the buses started