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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

Community Voting

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+360
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Top Comments

Archimedes001
759 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
2483 Posts
985 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
764 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 9, 2025
143 Posts
Joined Jul 2011
Apr 9, 2025
kancocorp
Apr 9, 2025
143 Posts
Unfortunately, Costco doesn't make 5 W 40
1
Apr 9, 2025
132 Posts
Joined Dec 2008
Apr 9, 2025
vuiskool
Apr 9, 2025
132 Posts
Quote from hollowpockets :
Ok.. well go get the engine number and Google it.

Thos is car oil. Small engine oil is typically different. You bought a honda engine, put the right oil in it.

and if you're a new homeowner.. my suggestion is to keep those books. you'll refer to them over time

Pro tip: every known brand manual is found online in PDF format. So you can toss those paper book manuals.
3
Apr 9, 2025
393 Posts
Joined Nov 2005
Apr 9, 2025
nocturnalmerkin
Apr 9, 2025
393 Posts
Quote from DealHunterNYC212 :
New homeowner here. I have the toro timemaster and a Ryobi power washer with a Honda engine. Is this good for those? If yes, which one? (I live in NY, if the temperature matters)
The Honda engine will outlive you even with the cheapest of conventional oil changed once every 100 hours. I think they tell you to do the first change early. The water pump seal will likely fail, easy fix just make sure you use the right size socket or pipe to push it in evenly. Source:me LOL. I have the Homelite with Honda GCV160 Honda engine. Given the cheap price of this oil I say go for it on both, can't go wrong. 5-30 is the preferred grade for most small engines, 0W-20 is thinner to promote better fuel economy and may not protect a smaller higher revving engine as well.
Apr 9, 2025
1 Posts
Joined Dec 2019
Apr 9, 2025
Neiladams
Apr 9, 2025
1 Posts
Love this oil. I use it in all of my vehicles.
Apr 9, 2025
764 Posts
Joined Oct 2012
Apr 9, 2025
patrocle
Apr 9, 2025
764 Posts

Our community has rated this post as helpful. If you agree, why not thank patrocle

Quote from patrocle :
Who does this costco oil? rebranded from where? I normally use the Penzoil 5w-20 Ultra full synthetic for Ram Truck
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
4
Pro
Apr 9, 2025
3,249 Posts
Joined Dec 2008
Apr 9, 2025
qkumbr
Pro
Apr 9, 2025
3,249 Posts
Quote from patrocle :
Who does this costco oil? rebranded from where? I normally use the Penzoil 5w-20 Ultra full synthetic for Ram Truck

Manufactured by Highline Warren LLC. I am reading the back of a jug in my garage.
Apr 9, 2025
39,096 Posts
Joined Nov 2005
Apr 9, 2025
Dr. J
Apr 9, 2025
39,096 Posts
Quote from DealHunterNYC212 :
New homeowner here. I have the toro timemaster and a Ryobi power washer with a Honda engine. Is this good for those? If yes, which one? (I live in NY, if the temperature matters)
The manual should show various oils with temperature service ranges. Unless you're operating the equipment in a hot environment (e.g. Phoenix) then 5W30 is going to give you your best year-round operation (e.g. when it's really cold, if you need that). Just be aware that small engines don't take a lot of oil so a 4 pack of 5Q is going to last a very very very long time.

I run 5W30 in my JDX530 but that's mostly because I use it to snowblow in the winter so it's a full year machine for me here in CT.

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Apr 9, 2025
39,096 Posts
Joined Nov 2005
Apr 9, 2025
Dr. J
Apr 9, 2025
39,096 Posts
Quote from patrocle :
Who does this costco oil? rebranded from where? I normally use the Penzoil 5w-20 Ultra full synthetic for Ram Truck
Warren, who also makes (private labels) oils for a bunch of other brands. Perfectly fine oil.
Apr 9, 2025
366 Posts
Joined Aug 2013
Apr 9, 2025
00821136
Apr 9, 2025
366 Posts
Quote from DealHunterNYC212 :
New homeowner here. I have the toro timemaster and a Ryobi power washer with a Honda engine. Is this good for those? If yes, which one? (I live in NY, if the temperature matters)

lol read your manuals....
Apr 9, 2025
14 Posts
Joined Mar 2018
Apr 9, 2025
linyang11879
Apr 9, 2025
14 Posts
Quote from anonman44 :
great deal but no 10w-30 Frown

5w-30 also works
2
Apr 9, 2025
124 Posts
Joined Oct 2019
Apr 9, 2025
PabIo
Apr 9, 2025
124 Posts
How much do you guys have stocked up ? First time buyer of this oil, long time oil changer
1
Apr 9, 2025
878 Posts
Joined Sep 2013
Apr 9, 2025
chrisaf69
Apr 9, 2025
878 Posts
I change my vehicle that only takes 5.x quarts once a year. Is this oil fine sitting on a shelf for 4-5 years?
Apr 9, 2025
145 Posts
Joined Nov 2015
Apr 9, 2025
stslimited84
Apr 9, 2025
145 Posts
Quote from deezer :
Cheaper per unit than in-warehouse.

Cheaper than warehouse including the current warehouse coupon?
Apr 9, 2025
603 Posts
Joined Jan 2015

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Apr 9, 2025
15 Posts
Joined May 2013
Apr 9, 2025
skrap1965
Apr 9, 2025
15 Posts
This is a great deal for DIY oil changers.

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