Here's a search for 12 packs of oil jugs [costco.com] if you'd rather get them.
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expired Posted by HappyPixel • Apr 9, 2025
Apr 9, 2025 10:45 AM
Item 1 of 2
Item 1 of 2
expired Posted by HappyPixel • Apr 9, 2025
Apr 9, 2025 10:45 AM
Costco Members: 4-Pk 5-Qt Kirkland Signature Full Synthetic Motor Oil (various)
+ Free Shipping$54 each
$70
Costco Wholesale
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The stuff sold at a price point (bargain basement) will meet API SP and dexos1 will have a treat rate of about 8.5% wt in the engine oil. Treat rate is the focus for products sold under a bid as the additive is sold by the ton, the less you use the cheaper the product. The more premium stuff will meet ACEA, MB 229, VW 501, etc. and have a treat rate of closer to 13%.
Now the clincher for me is that cheap additive package will pair with a cheap viscosity modifier (VM), the stuff that makes it a 0W-xx, usually some olefin copolymer (OCP). These are what I refer to as dirty polymers because they tend to leave more deposits as they break down (piston walls, skirts, rings, turbo bearings).
Those premium packages because they need to pass more stringent Euro specs will use a styrenic type polymer usually a star polymer which is a cleaner and more shear stable VM. This helps us keep the pistons cleaner = less scuffing, blow by, better power, better fuel economy, and these days more importantly a cleaner turbo as those are very hard on oil.
In the end the cheap stuff will not kill your engine, but much like living on ramen noodles and McDonalds it isn't going to make that engine stay at like new performance. I used to formulate this stuff before I retired so happy to answer questions.
Lower viscosity in the US is for CAFE reasons, not motor longevity.
page 8 and 9
https://engineoil.api.o
Warren Oil
https://www.warrenoil.c
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3:** P.M.Label Created
14-Apr: Order delayed email
17-Apr: Additional delay email
22-Apr: Order shipped via UPS
24-Apr: Order delivered in two boxes
I expected a special box with 4 jugs inside, but instead it was just two of the usual 2-pack boxes in one UPS box. Happy that the order was fulfilled without getting cancelled.
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On 4/22: "Due to the overwhelming response for this item, we regret to inform you that there will be a delay in fulfilling your order. Please be assured that your order will ship by the week of Apr 28, 2025 - May 2, 2025."
Kudos to Costco keeping me informed.
Basic engine oil = API SP/ GM dexos1
Better engine oil = Above + ACEA, VW, BMW or MB specifications attached.
If it meets Euro spec then those are likely to use high quality components as the low quality product can't pass those engine tests.
That said if you have a lease car or something you will trade in, well in that case, anything that meets the vis grades/specs recommended by the OEM as you won't care about losing a few hp or mpg.
If you are like me and keep things forever and are getting a little too old to keep wrenching every weekend... then choose one that meets those higher specs.
A question I have though, how would the Kirkland oil here compare to some of the "name brand" full synthetics like Mobil 1, Pennzoil Platinum, Castrol Edge, etc. Thinking those meeting API SP/GM Dexos 1 but not certified for ACEA. Is there a benefit to a more expensive full synthetic that meets the same requirement, or would we need to step up to something that meets the ACEA requirements to really see a benefit?
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