What 5W30 oil brand do you use in your CX-9?

I use Pennzoil Ultra Platinum in everything except my Porsches. And I also always, ALWAYS stick to OEM oil filters. My Silverado get an AC Delco, my mom's Grand Marquis gets a Motorcraft (because what else would an elderly church lady drive? ;)), and my Mazdas get Mazda filters. The CX-9 gets the two strip Turbo filter, the 2.0 CX-5 gets the single stripe.
 
I don't like the idea of stretching intervals in this car because we bought from new and plan to keep a long time. I've been mostly using Supertech Synthetic. GF-6 rating and regular price is very reasonable.I would have used Kirkland stuff which apparently is the exact same thing, but I like the 5L jug over the 4.73L size for the CX-9 oil changes. No thinking, dump the entire thing, and it brings it 3/4 up between the two dots. I end up doing it every four months, which works out to 6-7000 km (3800 - 4300 miles) interval.

I have only ever used the PY8W-14-302, made in Japan filters, bought a box from Partsouq, and then found my local dealership keeps a stash of them whenever they get them in, so bought a bunch.

I have tried Pennzoil Ultra Platinum, and also Valvoline Advanced when I saw them on sale. I have sent all my oil change samples away for analysis just for curiosity more than anything, but there has been no noticeable difference, nothing out of the ordinary (yes, I realize dissolved metals does not exactly equate to wear, but all the oils seem to be doing their job).



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I would have used Kirkland stuff which apparently is the exact same thing…
Has anybody ever seen comparative VOAs between Kirkland and other Warren brands? I've read that Costco goes beyond regular Top Tier standards with their gasoline, and I wonder if KS motor oil would get a better add pack than, say, Meijer oil.
 
Has anybody ever seen comparative VOAs between Kirkland and other Warren brands? I've read that Costco goes beyond regular Top Tier standards with their gasoline, and I wonder if KS motor oil would get a better add pack than, say, Meijer oil.

There is an old Project Farm where he compares the two and they're not 100% exact, but so close that it very well could be. He wasn't testing 0 mile samples, so hard to know. I guess Kirkland does have a different Dexos registration # vs Supertech/Amazon etc, but that could be a Costco thing also.

The PQIA site has some of the info, but I can't find regular Supertech Synthetic 5W30, only the high mileage stuff which is slightly different.

Kirkland is a better $/L price, especially when it goes on sale, but the jugs are just an annoying amount too small. Prob OK, but even with the 5L jug, it doesn't bring it all the way up to the top dot on the dipstick.
 
That's why I always keep a top-up quart or jug on hand. I've had one vehicle out of my last seven or so that took an even jug of any volume to fill the crank case.
 

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