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expired Posted by HappyPixel • Apr 9, 2025
expired Posted by HappyPixel • Apr 9, 2025

Costco Members: 4-Pk 5-Qt Kirkland Signature Full Synthetic Motor Oil (various)

+ Free Shipping

$54 each

$70

Costco Wholesale
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Deal Details
Costco Wholesale has for its Members: 4-Pack 5-Quart Kirkland Signature Full Synthetic Motor Oil (various) for $53.99 each. Shipping is free.

Thanks to community member HappyPixel for sharing this deal.

Available:

Editor's Notes

Written by citan359 | Staff
  • This offer is $10 less than the previous +79 Frontpage Deal from September 2024.
  • Please see the original post for additional details & give the WIKI and additional forum comments a read for helpful discussion.
  • If you don't have a Costco Warehouse Membership, you can sign-up here

Original Post

Written by HappyPixel
Community Notes
About the Poster
Deal Details
Community Notes
About the Poster
Costco Wholesale has for its Members: 4-Pack 5-Quart Kirkland Signature Full Synthetic Motor Oil (various) for $53.99 each. Shipping is free.

Thanks to community member HappyPixel for sharing this deal.

Available:

Editor's Notes

Written by citan359 | Staff
  • This offer is $10 less than the previous +79 Frontpage Deal from September 2024.
  • Please see the original post for additional details & give the WIKI and additional forum comments a read for helpful discussion.
  • If you don't have a Costco Warehouse Membership, you can sign-up here

Original Post

Written by HappyPixel

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Top Comments

Archimedes001
766 Posts
343 Reputation
LOL that's not really correct... Premium stuff can have up to 50% more additives and a better, cleaner VM. Yes there are mainly 4 large additive companies (many more medium and smaller) but let's take the biggest of those 4, Lubrizol. They sell many different additive packages so just because many blenders buy from them doesn't mean they buy the same package.

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.
Marlin1975
2506 Posts
989 Reputation
You can use 0w-20 just fine. Heck same motor outside the US calls for up to 5w-30

Lower viscosity in the US is for CAFE reasons, not motor longevity.
patrocle
765 Posts
112 Reputation
I guess here is the list where is coming from

page 8 and 9

https://engineoil.api.org/Directo...nyId=10297

Warren Oil
https://www.warrenoil.com/
Made by

323 Comments

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Apr 11, 2025
2,213 Posts
Joined Nov 2018
Apr 11, 2025
Gt7737
Apr 11, 2025
2,213 Posts
Quote from jimates :
What oil do you recommend in both premium and value line.

At $18 a jug this is the same value as SuperTech.
The Havoline 6 qt box is usually the best value.
This is $14.50 a jug vs $18.50 a jug for super tech . This oil will do just fine for low mileage interval changes like the other person noted 4-7k miles
Apr 11, 2025
773 Posts
Joined Aug 2006
Apr 11, 2025
gbcue
Apr 11, 2025
773 Posts
Anybody get a Delay Notification email?
Apr 11, 2025
6,569 Posts
Joined Mar 2011
Apr 11, 2025
ballershanelle
Apr 11, 2025
6,569 Posts
Quote from DealHunterNYC212 :
Nobody keeps the book
Wackos don't.
Apr 11, 2025
82 Posts
Joined Dec 2013
Apr 11, 2025
PeterM1200
Apr 11, 2025
82 Posts
Quote from Marlin1975 :
You can use 0w-20 just fine. Heck same motor outside the US calls for up to 5w-30

Lower viscosity in the US is for CAFE reasons, not motor longevity.
When we first bought our 2019 Toyota the dealer didn't have 0w-16 for the first 2 oil changes and used 0w-20. When I questioned it they said the engine hadn't changed just the oil spec.
Apr 11, 2025
268 Posts
Joined Dec 2007
Apr 11, 2025
lurking4deals
Apr 11, 2025
268 Posts
are the 12x 1 qt boxes cheaper in store?
Apr 11, 2025
2,506 Posts
Joined Dec 2008
Apr 11, 2025
Marlin1975
Apr 11, 2025
2,506 Posts
Quote from lurking4deals :
are the 12x 1 qt boxes cheaper in store?

Don't think most, if any stores, carries the quarts.

Stores I have been to have 2 5qt Jugs while online is 4 5qt jugs and 12pack quarts.

Online is cheaper this time for some reason.
Apr 11, 2025
2 Posts
Joined Sep 2024
Apr 11, 2025
BrightPlastic8246
Apr 11, 2025
2 Posts
no 0w16
1

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Apr 11, 2025
21 Posts
Joined Dec 2022
Apr 11, 2025
cometcal
Apr 11, 2025
21 Posts
Quote from oper :
Few years back - my friend fleet manager found 250 gallons of oil in 5qt jugs (Supertech ) The oil was 12 years old, he sent a sample to black stone for VOA and blackstone lab reported that the oil was as good as new and can be used without any problems.
Makes sense that synthetic oil has longer shelf life than 12 year old conventional oil.
Apr 11, 2025
40 Posts
Joined Feb 2018
Apr 11, 2025
NylonStringNinja
Apr 11, 2025
40 Posts
Quote from cometcal :
Makes sense that synthetic oil has longer shelf life than 12 year old conventional oil.
One main problem is the additives. You can look at the oil in a clear container and the oil will be milky looking and everything sitting on the bottom. If you cut open a jug like that you can scrape all the fallen out additives with your fingers and see it. I had a bunch of unopened polaris synthetic ATV oil and I figured synthetic oil lasts forever right. I was fixing up some ATVs and checked the oil before using it and ended up reading up on it. I ended up just recycling all of it. It was older than 12 years though and had been stored in the desert. A lot of it depends on storage conditions and age but I think to be sure if you inspect it and it looks good it probably is ok.
Apr 11, 2025
2,506 Posts
Joined Dec 2008
Apr 11, 2025
Marlin1975
Apr 11, 2025
2,506 Posts
Quote from BrightPlastic8246 :
no 0w16


ugh... as said many times that same motor calls for 0w-20 or even 5w-30 outside the US. You can use either of them just fine.
1
2
Apr 11, 2025
6 Posts
Joined Oct 2012
Apr 11, 2025
erikt15
Apr 11, 2025
6 Posts
Is it ok to put 5w 30 for Audi rs3 2024?
Apr 12, 2025
659 Posts
Joined Nov 2013
Apr 12, 2025
iheartdeals123
Apr 12, 2025
659 Posts
Quote from Archimedes001 :
LOL that's not really correct... Premium stuff can have up to 50% more additives and a better, cleaner VM. Yes there are mainly 4 large additive companies (many more medium and smaller) but let's take the biggest of those 4, Lubrizol. They sell many different additive packages so just because many blenders buy from them doesn't mean they buy the same package.

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.
Which brands would you recommend/not recommend?

also, I bought this Kirkland oil about 4 years ago and the rest is sitting in storage. do you know if oil expires? if so how badly
Apr 12, 2025
461 Posts
Joined Oct 2010
Apr 12, 2025
Nessism
Apr 12, 2025
461 Posts
Quote from gbcue :
Anybody get a Delay Notification email?
I did. Living in So Calif. Shipping next week, or so the email states. I'm good with that. This deal is way too good to pass up.
Apr 12, 2025
2,578 Posts
Joined May 2018
Apr 12, 2025
Timless
Apr 12, 2025
2,578 Posts
Quote from NylonStringNinja :
One main problem is the additives. You can look at the oil in a clear container and the oil will be milky looking and everything sitting on the bottom. If you cut open a jug like that you can scrape all the fallen out additives with your fingers and see it. I had a bunch of unopened polaris synthetic ATV oil and I figured synthetic oil lasts forever right. I was fixing up some ATVs and checked the oil before using it and ended up reading up on it. I ended up just recycling all of it. It was older than 12 years though and had been stored in the desert. A lot of it depends on storage conditions and age but I think to be sure if you inspect it and it looks good it probably is ok.
New Pennzoil has that stuff at the bottom. They say to just shake it up.

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Apr 12, 2025
1,191 Posts
Joined Nov 2010
Apr 12, 2025
Justhathought
Apr 12, 2025
1,191 Posts
Pennzoil sucks bad
3

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