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frontpageSUCHaDEAL posted Feb 07, 2026 02:58 PM
frontpageSUCHaDEAL posted Feb 07, 2026 02:58 PM

5-Qt Castrol Edge High Mileage Advanced Full Synthetic Motor Oil (0W-20)

w/ Subscribe & Save

$21

$29

27% off
Amazon
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Amazon has 5-Quart Castrol Edge High Mileage Advanced Full Synthetic Motor Oil (0W-20) for $22.32 - 5% when you check out via Subscribe & Save = $21.20. Shipping is free w/ Prime or on $35+ orders.

Thanks to Community Member SUCHaDEAL for finding this deal. About this item:
  • Phosphorus Replacement Technology to help extend the life of the emission system
  • Reduces leaks, oil burnoff and power robbing deposits
  • 15,000 miles between oil changes*
  • Meets or exceeds the following specifications: API SP/SN PLUS/SN/SM | ILSAC GF-6 | Meets engine test requirements of Chrysler MS 6395 | Meets Ford WSS-M2C947-B1 | Meets Ford WSS-M2C962-A2
  • *Or one year, whichever comes first

Editor's Notes

Written by SubZero5 | Staff
  • About this deal:
    • Our research indicates that this deal is $6.28 less (23% savings) than the next best available price from a reputable merchant with prices starting from $27.48 at the time of this posting.
  • About this product:
    • Rating of 4.8/5 from 1,200+ Amazon customer reviews.
  • About this store:

Original Post

Written by SUCHaDEAL
Product Info
Community Notes
About the Poster
Deal Details
Product Info
Community Notes
About the Poster
Amazon has 5-Quart Castrol Edge High Mileage Advanced Full Synthetic Motor Oil (0W-20) for $22.32 - 5% when you check out via Subscribe & Save = $21.20. Shipping is free w/ Prime or on $35+ orders.

Thanks to Community Member SUCHaDEAL for finding this deal. About this item:
  • Phosphorus Replacement Technology to help extend the life of the emission system
  • Reduces leaks, oil burnoff and power robbing deposits
  • 15,000 miles between oil changes*
  • Meets or exceeds the following specifications: API SP/SN PLUS/SN/SM | ILSAC GF-6 | Meets engine test requirements of Chrysler MS 6395 | Meets Ford WSS-M2C947-B1 | Meets Ford WSS-M2C962-A2
  • *Or one year, whichever comes first

Editor's Notes

Written by SubZero5 | Staff
  • About this deal:
    • Our research indicates that this deal is $6.28 less (23% savings) than the next best available price from a reputable merchant with prices starting from $27.48 at the time of this posting.
  • About this product:
    • Rating of 4.8/5 from 1,200+ Amazon customer reviews.
  • About this store:

Original Post

Written by SUCHaDEAL

Community Voting

Deal Score
+78
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Price Intelligence

Model: Castrol Edge High Mileage 0W-20 Advanced Full Synthetic Motor Oil, 5 Quarts

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Sort: Lowest to Highest | Last Updated 3/4/2026, 12:56 AM
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Top Comments

SDSummerDay
5138 Posts
737 Reputation
Just FYI — none of the "true synthetic" oils you're getting in the U.S. market at this price point are actually true synthetics.

That all goes back to a famous lawsuit between Mobil and Castrol in the 1990s (yes, that Castrol).

Base oils are traditionally classified into five groups. Groups I, II, and III are derived from conventional crude oil. Groups IV and V are what were originally considered real synthetics — chemically engineered hydrocarbons like PAO, esters, polyglycols, or silicone. Mobil pioneered much of this technology.

For a long time, only Group IV and V oils could legally be labeled "synthetic," and they commanded a premium because they retained their physical properties far better.

In the 1990s, Castrol started using highly processed Group III base oils and marketing them as synthetic. Mobil sued, arguing that Group III was still conventional oil. Mobil lost. Castrol's argument was that Group III oils are so heavily processed that calling them synthetic was justified.

Fast forward to today: in the U.S. (but not in places like Germany or Japan), "synthetic" can legally mean Group III, IV, or V. So "100% synthetic" can be 100% Group III — which pre-1990 would not have been considered synthetic at all.

"Synthetic blend," meanwhile, can be basically any mix of Group I–II with Group III–V.

So yes — Castrol Edge High Mileage Advanced Full Synthetic made in the U.S. is, you guessed it, Group III. But Castrol Edge Full Synthetic made in Germany (even with the same name) is typically a true Group IV oil.

Given how screwed up the labeling system is, I just stick with Costco.

65 Comments

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Feb 08, 2026 01:40 AM
736 Posts
Joined Jul 2007
onlycashFeb 08, 2026 01:40 AM
736 Posts
Quote from SDSummerDay :
Just FYI — none of the "true synthetic" oils you're getting in the U.S. market at this price point are actually true synthetics....
I just stick with Costco.
Quote from handogg :
Do you recommend sticking with Mobil1 ?
Quote from Macseed07 :
Thank you for taking the time to inform us.
Quote from M5Rahul :
Thank you for this! nod
Quote from spydrmon :
Sounds like a great mid tier performance and price point for those who can't afford true synthetic but want better than conventional in their engine.
Quote from dnabrice :
Any thoughts on why Costco is good?
Quote from food1313 :
How come group is not listed here if it's so important?
https://www.mobil.com/en/lubrican...il-1-0w-20
Quote from MostBased :
Thanks for the info! I had to ask how this compares to my go-to Pennzoil ultra platinum, and here it is:..
Quote from Mr. Sparkles :
Review on costco says their's are group 3 too.
Quote from DealsSkills :
"(but not in places like Germany or Japan)" ....
Quote from SmartAlpaca4442 :
Debate raged then, and still rages today. You can find all kinds of purists populating Internet forums who refuse to recognize Group III oils as "synthetics." For them, it's PAO or nothing...

If you're looking for some good, honest info on motor oil, I would suggest you watch a few of Lake Speed's videos on YouTube.


https://www.youtube.com/@themotoroilgeek


.
1
Feb 08, 2026 02:17 AM
2,231 Posts
Joined Jan 2005
bud8jrFeb 08, 2026 02:17 AM
2,231 Posts
Quote from SUCHaDEAL :
if you say so.
Stop by and ask them.
Feb 08, 2026 02:52 AM
2,241 Posts
Joined Oct 2008
asukaFeb 08, 2026 02:52 AM
2,241 Posts
Quote from andy50 :
What mileage is considered high milage
I only recommend high mileage oil if:

* You have leaks
* Oil analysis of used oil has found metals in the oil
* You're selling the car and just want it to last a bit longer with less risk

I recommend doing an oil analysis every couple of years unless/until they find someone, or you have a rare car. Then do it 1-2 times a year or more if needed.

High mileage oil can clog your catalytic converter needlessly. Most engines today don't need it unless there's a good reason.
Last edited by asuka February 7, 2026 at 07:54 PM.
Feb 08, 2026 03:01 AM
386 Posts
Joined Sep 2017
limocadFeb 08, 2026 03:01 AM
386 Posts
Quote from PurpleCrowMan :
According to Goog AI: Top Group IV (PAO) and Group V (Ester) full synthetic motor oils in the USA offer superior thermal stability, oxidation resistance, and wear protection. Leading brands using these high-performance base stocks include AMSOIL Signature Series, Mobil 1 Extended Performance/ESP, Royal Purple, and Liqui Moly (specifically Longtime High Tech). These oils are designed for extreme temperatures and high-performance engines.

As long as you change the oil every 6 months or 5K miles it doesn't matter if you use Costco or any brand of synthetic oil. This is for non commercial use. For commercial use, change oil every 3K miles as commercial vehicles like taxis and limos idle a lot. Regular maintenance will keep your vehicle running way more than neglected vehicles of the same brand, model and age.
Last edited by limocad February 7, 2026 at 08:05 PM.
Feb 08, 2026 03:11 AM
2,241 Posts
Joined Oct 2008
asukaFeb 08, 2026 03:11 AM
2,241 Posts
Quote from limocad :
As long as you change the oil every 6 months or 5K miles it doesn't matter if you use Costco or any brand of synthetic oil. This is for non commercial use. For commercial use, change oil every 3K miles as commercial vehicles like taxis and limos idle a lot. Regular maintenance will keep your vehicle running way more than neglected vehicles of the same brand, model and age.
Exception is if you have a car with issues. L87, Ecotec, etc. Know your car.

Research if your car needs a 3k change interval. Camshaft, timing chains, etc. Manufacturers often can screw this stuff up so even a hint of dirt in the oil can break them.
Feb 08, 2026 04:20 AM
6,970 Posts
Joined Jan 2006
MPoWeRM3Feb 08, 2026 04:20 AM
6,970 Posts
Quote from bozoskeletonz :
Walmart was $28 for me. Also, Amazon showed up on the rebate form for me.
What zip code you use for Amazon on the form?
Feb 08, 2026 05:16 AM
3,091 Posts
Joined Dec 2010
radarsFeb 08, 2026 05:16 AM
3,091 Posts
Is there any rebate for it?

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Feb 08, 2026 06:10 AM
2,231 Posts
Joined Jan 2005
bud8jrFeb 08, 2026 06:10 AM
2,231 Posts
Quote from limocad :
As long as you change the oil every 6 months or 5K miles it doesn't matter if you use Costco or any brand of synthetic oil. This is for non commercial use. For commercial use, change oil every 3K miles as commercial vehicles like taxis and limos idle a lot. Regular maintenance will keep your vehicle running way more than neglected vehicles of the same brand, model and age.
You are pretty much right. From my experience worked at UPS for 30+ years, they use conventional 10w30 or maybe just straight 30 weight that they bought by the barrels, probably got it straight from the refinery in trailer loads. Probably same with the postal service, FedEx or garbage trucks. They don't care about leaks. Sure there were lots of puddles in the warehouse and they refill them once or twice a week. They don't care about additive packages.

Of course a lot different for personal vehicles. A lot of BS with marketing especially with the high mileage or whatever.

In my experience with our hondas j37 or j35 engines with 180k+ miles, they get at least from our experience from either the thin valve covers rotting through or valve cover gaskets and VTech solenoid gaskets leaking which is a very common issue.

Bottom line is get the what they consider full synthetic which suspenseds the solids and a magnetic drain plug or put a magnet on the oil filter over conventional oil.

After viewing many YouTube videos I decided to try the Valvoline restore and protect which slowly takes out the varnish and sludge. Might take one or two oil changes then I'll go back to the regular full synthetic for cheap like I posted earlier for $15 for a 5 gallon jug from tractor supply now.

Basic costco, tractor supply and walmart store brands "full" or fool(what I call them)synthetic oils are all made by Warren. I bet minimal or no additive packages in each. Same stuff different packaging.

Mostly all about the leakage at the mileage.

They call for the same engine 5W20 in the US and 5W30 in Europe, Asia, and Australia. It's all about the CAFE standards along with shutting the engine off at stop lights to get the mileage up for US government standards. Total BS.
Feb 08, 2026 06:20 AM
216 Posts
Joined Jan 2018
dinhscotFeb 08, 2026 06:20 AM
216 Posts
There a $10 Castrol Rebate that work with Amazon order. Amazon is on the rebate page drop down list
Feb 08, 2026 06:32 AM
2,231 Posts
Joined Jan 2005
bud8jrFeb 08, 2026 06:32 AM
2,231 Posts
Quote from bud8jr :
You are pretty much right. From my experience worked at UPS for 30+ years, they use conventional 10w30 or maybe just straight 30 weight that they bought by the barrels, probably got it straight from the refinery in trailer loads. Probably same with the postal service, FedEx or garbage trucks. They don't care about leaks. Sure there were lots of puddles in the warehouse and they refill them once or twice a week. They don't care about additive packages. Of course a lot different for personal vehicles. A lot of BS with marketing especially with the high mileage or whatever. In my experience with our hondas j37 or j35 engines with 180k+ miles, they get at least from our experience from either the thin valve covers rotting through or valve cover gaskets and VTech solenoid gaskets leaking which is a very common issue. Bottom line is get the what they consider full synthetic which suspenseds the solids and a magnetic drain plug or put a magnet on the oil filter over conventional oil. After viewing many YouTube videos I decided to try the Valvoline restore and protect which slowly takes out the varnish and sludge. Might take one or two oil changes then I'll go back to the regular full synthetic for cheap like I posted earlier for $15 for a 5 gallon jug from tractor supply now. Basic costco, tractor supply and walmart store brands "full" or fool(what I call them)synthetic oils are all made by Warren. I bet minimal or no additive packages in each. Same stuff different packaging. Mostly all about the leakage at the mileage. They call for the same engine 5W20 in the US and 5W30 in Europe, Asia, and Australia. It's all about the CAFE standards along with shutting the engine off at stop lights to get the mileage up for US government standards. Total BS.
As far as starters and brake pads are concerned, they obviously have a higher specification. The brake pads were like double thick kind of like nascar short track races. I've seen them both.
Feb 08, 2026 06:45 AM
523 Posts
Joined May 2005
Drift MotionFeb 08, 2026 06:45 AM
523 Posts
wish theres more deal on 40w, these 20w and 30w ones can be bought at costco for $36 for two all the time
Feb 08, 2026 08:35 AM
318 Posts
Joined Jun 2018
J1336Feb 08, 2026 08:35 AM
318 Posts
Quote from onlycash :






















If you're looking for some good, honest info on motor oil, I would suggest you watch a few of Lake Speed's videos on YouTube.


https://www.youtube.com/@themotoroilgeek


.
yea he's great
2
Feb 08, 2026 11:01 AM
36 Posts
Joined Apr 2018
-Eli-Feb 08, 2026 11:01 AM
36 Posts
Quote from SDSummerDay :
Just FYI — none of the "true synthetic" oils you're getting in the U.S. market at this price point are actually true synthetics.

That all goes back to a famous lawsuit between Mobil and Castrol in the 1990s (yes, that Castrol).

Base oils are traditionally classified into five groups. Groups I, II, and III are derived from conventional crude oil. Groups IV and V are what were originally considered real synthetics — chemically engineered hydrocarbons like PAO, esters, polyglycols, or silicone. Mobil pioneered much of this technology.

For a long time, only Group IV and V oils could legally be labeled "synthetic," and they commanded a premium because they retained their physical properties far better.

In the 1990s, Castrol started using highly processed Group III base oils and marketing them as synthetic. Mobil sued, arguing that Group III was still conventional oil. Mobil lost. Castrol's argument was that Group III oils are so heavily processed that calling them synthetic was justified.

Fast forward to today: in the U.S. (but not in places like Germany or Japan), "synthetic" can legally mean Group III, IV, or V. So "100% synthetic" can be 100% Group III — which pre-1990 would not have been considered synthetic at all.

"Synthetic blend," meanwhile, can be basically any mix of Group I–II with Group III–V.

So yes — Castrol Edge High Mileage Advanced Full Synthetic made in the U.S. is, you guessed it, Group III. But Castrol Edge Full Synthetic made in Germany (even with the same name) is typically a true Group IV oil.

Given how screwed up the labeling system is, I just stick with Costco.
Costco's Kirkland Signature Full Synthetic is a fantastic oil, but it is manufactured by Warren Distribution and is almost entirely Group III base oil. By the your own logic, you are buying the very thing you are complaining about.
1
Pro
Feb 08, 2026 11:03 AM
1,355 Posts
Joined Dec 2010
drezhere
Pro
Feb 08, 2026 11:03 AM
1,355 Posts
They did not honor the WNBA promotion for me last year, so I never received my rebate gift cards. I carefully followed the rules. I am not giving this company my money.

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Feb 08, 2026 01:53 PM
20 Posts
Joined Sep 2024
StrongLake4786Feb 08, 2026 01:53 PM
20 Posts
Quote from limocad :

This is probably the same as Kirkland, Walmart and Amazon oil.
The Traveller doesn't list Dexos certification. I wonder if the listing is old, or if this is blended with a different formula than Kirkland & Supertech.

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