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expiredphoinix | Staff posted Mar 25, 2026 11:34 AM
expiredphoinix | Staff posted Mar 25, 2026 11:34 AM

5-Qt Castrol GTX Full Synthetic Motor Oil (5W-20)

w/ S&S

$19

$25

24% off
Amazon
19 Comments 7,973 Views
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Deal Details
Amazon has 5-Quart Castrol GTX Full Synthetic Motor Oil (5W-20) for $20.37 - 5% ($1.02) when you check out via Subscribe & Save = $19.35. Shipping is free with Prime or on $35+ orders.

Note: You have the flexibility to manage your Subscribe & Save subscription at any time after your order ships. View Subscribe & Save filler items and our current Subscribe & Save Frontpage deals to unlock up to extra 15% savings when you have 5 or more items in your current monthly subscription.

Thanks to Deal Hunter phoinix for finding this deal.

Product Description:
  • 6X better wear protection on critical engine parts than industry standards**
  • 1.3X better sludge protection than industry standards*
  • 3X Stronger against viscosity breakdown than leading full synthetic^
  • Protection for 10,000 miles between oil changes
  • Meets or exceeds the following specifications: API SP/SN PLUS/SN | ILSAC GF-6 | Meets Ford WSS-M2C945-B1 | Meets Ford WSS-M2C960-A1 |

Editor's Notes

Written by Discombobulated | Staff
  • About this Deal:
    • Our research indicates that this offer is $4.61 lower (19.2% savings) than the next best available price from a reputable merchant with prices starting from $23.96.
  • About this Product:
    • Rating of 4.9 stars overall from over 1,900 customer reviews.
  • About this Store:

Original Post

Written by phoinix | Staff
Product Info
Community Notes
About the Poster
Deal Details
Product Info
Community Notes
About the Poster
Amazon has 5-Quart Castrol GTX Full Synthetic Motor Oil (5W-20) for $20.37 - 5% ($1.02) when you check out via Subscribe & Save = $19.35. Shipping is free with Prime or on $35+ orders.

Note: You have the flexibility to manage your Subscribe & Save subscription at any time after your order ships. View Subscribe & Save filler items and our current Subscribe & Save Frontpage deals to unlock up to extra 15% savings when you have 5 or more items in your current monthly subscription.

Thanks to Deal Hunter phoinix for finding this deal.

Product Description:
  • 6X better wear protection on critical engine parts than industry standards**
  • 1.3X better sludge protection than industry standards*
  • 3X Stronger against viscosity breakdown than leading full synthetic^
  • Protection for 10,000 miles between oil changes
  • Meets or exceeds the following specifications: API SP/SN PLUS/SN | ILSAC GF-6 | Meets Ford WSS-M2C945-B1 | Meets Ford WSS-M2C960-A1 |

Editor's Notes

Written by Discombobulated | Staff
  • About this Deal:
    • Our research indicates that this offer is $4.61 lower (19.2% savings) than the next best available price from a reputable merchant with prices starting from $23.96.
  • About this Product:
    • Rating of 4.9 stars overall from over 1,900 customer reviews.
  • About this Store:

Original Post

Written by phoinix | Staff

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+35
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19 Comments

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Mar 25, 2026 01:37 PM
76 Posts
Joined May 2019
dealwolf389Mar 25, 2026 01:37 PM
76 Posts
Thanks OP .... Great Deal !!!!
In for 2

[IMG]https://media3.giphy.com/media/v1.Y2lkPTI5MDMyOTZheXR1cWIxdGVjbHh0Y2hmcDc0a3MyeTQ0eDZkMTNwbzh3M3Jkam8xMiZlcD12MV9naWZzX3NlYXJjaCZjdD1n/oBPOP48aQpIxq/giphy.gif[/IMG]
Mar 25, 2026 02:48 PM
68 Posts
Joined Apr 2017
gmvalentineMar 25, 2026 02:48 PM
68 Posts
Looks like the 5w-30 is $18.33 with S&S.
Pro
Mar 25, 2026 03:13 PM
4,690 Posts
Joined Dec 2004
Deal Explorer
Pro
Mar 25, 2026 03:13 PM
4,690 Posts
It's a good deal. But, I'd still spend the few extra bucks and get the Castrol Edge.
Mar 25, 2026 04:23 PM
942 Posts
Joined Nov 2009
mrgamersMar 25, 2026 04:23 PM
942 Posts
Costco synthetic or Castrol GTX?
Mar 25, 2026 04:27 PM
10,825 Posts
Joined Nov 2010
youra6Mar 25, 2026 04:27 PM
10,825 Posts
Quote from mrgamers :
Costco synthetic or Castrol GTX?
Look at the manual on your car. If there are specific certs or APN requirements, just buy the oil that meets them.
Mar 25, 2026 04:56 PM
10,825 Posts
Joined Nov 2010
youra6Mar 25, 2026 04:56 PM
10,825 Posts
Wish they still sold 5w-50 in the 5 gallon container.
Picked up 4 of the Dexos 5w-30 for 20 bucks. Have a feeling oil is gonna get really expensive.
Mar 26, 2026 04:49 AM
2,372 Posts
Joined Oct 2008
asukaMar 26, 2026 04:49 AM
2,372 Posts
API SP not SQ. Only Ford certs.

Man Castrol really blew it this time with the latest gen.

Okay if you have a car from 2005 or earlier with no turbo or timing chain. But yeah, this stinks.
1

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Mar 26, 2026 04:51 AM
2,372 Posts
Joined Oct 2008
asukaMar 26, 2026 04:51 AM
2,372 Posts
Quote from youra6 :
Wish they still sold 5w-50 in the 5 gallon container.
Picked up 4 of the Dexos 5w-30 for 20 bucks. Have a feeling oil is gonna get really expensive.

Grabbed the Mobil1 Euro 3-pack deal for that reason. And sure enough it was the new formation with the old pre-Dexos-approval label. Best of both worlds. Latest product without the marketing fluff.
Mar 26, 2026 04:53 AM
2,372 Posts
Joined Oct 2008
asukaMar 26, 2026 04:53 AM
2,372 Posts
Quote from youra6 :
Look at the manual on your car. If there are specific certs or APN requirements, just buy the oil that meets them.

Uh... Depends. If you want your car to last 300,000 miles, go for the latest spec with the thickest oil permitted.

That would be API SQ today.

Newer API spec means better oil that protects engine components better.

(This oil is API SP, basically one spec earlier).
1
Mar 26, 2026 10:40 AM
1,099 Posts
Joined Dec 2004
mustsav3Mar 26, 2026 10:40 AM
1,099 Posts
Good price for full synthetic 5 quarts.
Mar 26, 2026 05:05 PM
815 Posts
Joined Oct 2014
turboc20Mar 26, 2026 05:05 PM
815 Posts
Just learnt this is legally "full synthetic", but not chemically.

Yeah it might be as good as full synthetic, but consider the cost to make them, it's not a deal.
Mar 26, 2026 05:19 PM
2,139 Posts
Joined Dec 2005
nohomers1Mar 26, 2026 05:19 PM
2,139 Posts
Has a $10 rebate as well good through the end of this month!
Mar 26, 2026 06:09 PM
256 Posts
Joined Oct 2010
wh0liganMar 26, 2026 06:09 PM
256 Posts
Quote from gmvalentine :
Looks like the 5w-30 is $18.33 with S&S.

Did not find this. Care to share a link?
Sr. Moderator
Mar 26, 2026 06:10 PM
4,699 Posts
Joined Dec 2004
missiethegal
Sr. Moderator
Mar 26, 2026 06:10 PM
4,699 Posts
Quote from wh0ligan :
Did not find this. Care to share a link?
maybe this one?
https://www.amazon.com/Castrol-Sy...B09M982T3B

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Mar 27, 2026 12:26 AM
138 Posts
Joined Nov 2015
finalresortMar 27, 2026 12:26 AM
138 Posts
Quote from nohomers1 :
Has a $10 rebate as well good through the end of this month!
Where do you see the rebate offer? Link?

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