No it doesn’t. Use what the manufacturer specifies. My 09 Focus has 208k or 209k and has only ever had the manufacturer specified 5W-20 of whatever manufacturer/filter combo is on sale at Autozone when I go to get supplies (so it’s had Motorcraft, Castrol, Mobil 1, Quaker State, etc.). I haven’t needed to repair the engine or take it apart either 
You had a leaking seal, you put in an oil that swells seals and stopped the leak. Great. This has nothing to do with whether any of those tested oils are actually any “better” for a car that gets normal oil changes.
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We had one and maybe still lurks. Doc was our resident petroleum engineer/expert. From Canada, world-wide experience, knew all about refining, etc. Just like you could go to the bank with what Transman said about transmissions.
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It’s just another data point to consider. If you watched all the other tests, there really wasn’t as much difference between the oils as it looked like on the graphs. They were all so close that for my money, I’m going to be using that Costco oil at $25/10qts. I’m not going for a million mile vehicle.
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IIRC, @texases is a retired petroleum engineer. He might not want to get more into this discussion than he is already though. I think the discussion about which synthetic oil to use isn’t all that important. Unless your car is new enough to require synthetic oil, any group 1 or 2 oil from a major manufacturer and certified by the auto manufacturer will be fine. Newer vehicles that require synthetic oil will be fine with group 3 or 4 oils, subject to car manufacturer approval by third party designation (like API).
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Make that a ‘not quite retired’ petroleum engineer. But I work in the ‘upstream’ part of the industry, how to get more oil and gas out of the ground.
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Pls see my post earlier on prices #29 - AMS XL is cheaper than M1 by a few bucks. Prices are:
M1 AMS XL AMS Sig
$32 $28 $39
AMS free ship if u spend $100
For $7 more, you save on oil filter assuming you change oil 12k interval instead of 5k. Its worth it + environment.
So if you are driving 25k or more a year, then AMS Sig at $39 is worth it .
M1: ($32 + filter + labor) x 5 = $160 + $(5 filter + 5 labor)
AMS Sig: $39 + filter + labor
Saving = $121 + (4 filter + 4 labor) for every 25k you drive
Same way you would save with AMS XL if you drive 10k or more each year.
Update:
I am assuming that you change oil by time too - ie at least every year or when you hit the mile limit, say 12k or 1 year which ever comes first
How often you changed the oil?
You mean Kirkland branded Full Syn oil? How does this compare with M1?
$25/10qts is regular price?
What is API stand for?
Is this printed on the car somewhere - otherwise any easy way to find this info? I never heard API when it comes to oil?
API is the American Petroleum Institute. They’re involved in setting specifications, among other things. For crude oil there is a scale of density measure in ‘degrees API’, it’s kind of backwards, a low-density oil might be a 45 degree API oil, while a ‘heavy oil’ might be a 10 degree API. But this is for crude oils, not motor oil.
Here’s a guide to API’s motor oil specs:
They work with the SAE (Society of Automotive Engineers) to set the specs.
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every 5k miles
I edited post #67 to include some cost perspective - did I miss anything there?
It looks to me people drive 10k or more in a year and are willing to extend the change interval, can save money with AMS XL or Signature. And of course environment.
Good Grief , this is still going on !!! 
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I tracked it down to $30/10 gal regular price - who is the vendor? Amazon uses Super Tech which is better than M1
Post #47 by @keith - I should mark as one of the solution
The author of the video - I have seen him on others - I would think he is reliable - however it is always possible to miss something in a test like that.
But we had a lot of positives of AMS products + they give 12k, and 25k clearly stated. Whereas M1 20k oil is only if you are using it on freeway (its there in their fine print).
Thanks all for your contribution and helping with knowledge discovery. So many great perspective especially those just change oil frequently and kept the car well.
Supertech, Amazon Basic and Kirkland (Costco) are all made by the same manufacturer, Warren Distribution. Kirkland is $29.99 at Costco.com, $24.99 in the store. I guess the free shipping is really $5.00.
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Where are you getting your prices from? AMS XL is $9.50/qt. Mobil-1 at Walmart (TODAY) is $22.50 for 5 qts. That’s less then half the price.
AMS is around 97
M1 is around 87
M1: consensus seems change every 5k.
AMS XL 12k and AMS Sig 25k
You save a ton with AMS if you drive a lot. See my post #67. Plus environment.
I would never do that, regardless of whether AMS offers some sort of guarantee. Do they?