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frontpageSUCHaDEAL posted Apr 29, 2026 11:51 AM
frontpageSUCHaDEAL posted Apr 29, 2026 11:51 AM

5-qt Castrol GTX High Mileage Synthetic Blend Motor Oil (10W-30)

w/ S&S

$14

$24

41% off
Amazon
23 Comments 7,928 Views
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Deal Details
Amazon has 5-qt Castrol GTX High Mileage Synthetic Blend Motor Oil (10W-30) on sale for $14.95 - $0.75 (5% Subscribe & Save discount) = $14.20. Shipping is free with Prime or on $35+ orders.

Thanks to community member SUCHaDEAL for finding this deal.

Available: Features:
  • Phosphorus Replacement Technology extends emission system life
  • Superior dispersancy fights sludge build up inside engine
  • Seal conditioners help reduce oil leaks from aging gaskets
  • Advanced additives prevent engine wear and improve fuel economy
  • Meets API SP/SN PLUS/SN/SM and ILSAC GF-6 specifications

Editor's Notes

Written by megakimcheelove | Staff
  • This offer matches previous Front Page deal that earned 53+ thumbs up.
  • This offer matches previous Front Page deal that earned 37+ thumbs up.
  • Don't have Amazon Prime? Students can get a free 6-Month Amazon Prime trial with free 2-day shipping, unlimited video streaming & more.
  • If you're not a student, there's also a free 1-Month Amazon Prime trial available.
No Longer Available:

Original Post

Written by SUCHaDEAL
Product Info
Community Notes
About the Poster
Deal Details
Product Info
Community Notes
About the Poster
Amazon has 5-qt Castrol GTX High Mileage Synthetic Blend Motor Oil (10W-30) on sale for $14.95 - $0.75 (5% Subscribe & Save discount) = $14.20. Shipping is free with Prime or on $35+ orders.

Thanks to community member SUCHaDEAL for finding this deal.

Available: Features:
  • Phosphorus Replacement Technology extends emission system life
  • Superior dispersancy fights sludge build up inside engine
  • Seal conditioners help reduce oil leaks from aging gaskets
  • Advanced additives prevent engine wear and improve fuel economy
  • Meets API SP/SN PLUS/SN/SM and ILSAC GF-6 specifications

Editor's Notes

Written by megakimcheelove | Staff
  • This offer matches previous Front Page deal that earned 53+ thumbs up.
  • This offer matches previous Front Page deal that earned 37+ thumbs up.
  • Don't have Amazon Prime? Students can get a free 6-Month Amazon Prime trial with free 2-day shipping, unlimited video streaming & more.
  • If you're not a student, there's also a free 1-Month Amazon Prime trial available.
No Longer Available:

Original Post

Written by SUCHaDEAL

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+48
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Model: Castrol GTX High Mileage 10W-30 Synthetic Blend Motor Oil, 5 Quarts

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Top Comments

Kalpesh1972
17 Posts
10 Reputation
Why would someone buy a synthetic blend when Costco sells full synthetic at almost same price. Of course one will need a membership though. I think most cars mandates use of full synthetic.

23 Comments

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Apr 29, 2026 08:44 PM
17 Posts
Joined Mar 2019
Kalpesh1972Apr 29, 2026 08:44 PM
17 Posts
Why would someone buy a synthetic blend when Costco sells full synthetic at almost same price. Of course one will need a membership though. I think most cars mandates use of full synthetic.
1
2
Apr 30, 2026 12:00 PM
312 Posts
Joined Dec 2010
Vanhook2Apr 30, 2026 12:00 PM
312 Posts
Quote from Kalpesh1972 :
Why would someone buy a synthetic blend when Costco sells full synthetic at almost same price. Of course one will need a membership though. I think most cars mandates use of full synthetic.
Post the link please.The lowest price I see for any oil 34.99 + tax.
1
Apr 30, 2026 12:36 PM
4,316 Posts
Joined Sep 2010
stegallApr 30, 2026 12:36 PM
4,316 Posts
Dang good prices, but I have no need. Repped.
Apr 30, 2026 10:19 PM
79 Posts
Joined Oct 2025
FancyTable532Apr 30, 2026 10:19 PM
79 Posts
I like Castrol.
Apr 30, 2026 10:38 PM
359 Posts
Joined Jan 2021
BeautifulLake409Apr 30, 2026 10:38 PM
359 Posts
Quote from Kalpesh1972 :
Why would someone buy a synthetic blend when Costco sells full synthetic at almost same price. Of course one will need a membership though. I think most cars mandates use of full synthetic.
You're so fos
1
1
Apr 30, 2026 10:39 PM
140 Posts
Joined Nov 2010
delliedogApr 30, 2026 10:39 PM
140 Posts
great oil ! Never thought I'd say this
Apr 30, 2026 10:56 PM
591 Posts
Joined Jul 2016
ssen2004Apr 30, 2026 10:56 PM
591 Posts
Quote from Vanhook2 :
Post the link please.The lowest price I see for any oil 34.99 + tax.
Today at Costco warehouse price is $29.99 after discounts for 2 jars of Kirkland full synchetic various 0-20/5-20 and more

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Apr 30, 2026 11:46 PM
10 Posts
Joined Apr 2019
uproApr 30, 2026 11:46 PM
10 Posts
Get it while oil is cheap
Apr 30, 2026 11:50 PM
916 Posts
Joined Sep 2013
chrisaf69Apr 30, 2026 11:50 PM
916 Posts
Do yourself a favor and just pay the few bucks more for full synthetic. Your engine will thank you many miles down the road.
May 01, 2026 12:26 AM
450 Posts
Joined Mar 2009
djdumbbiiMay 01, 2026 12:26 AM
450 Posts
Quote from Kalpesh1972 :
Why would someone buy a synthetic blend when Costco sells full synthetic at almost same price. Of course one will need a membership though. I think most cars mandates use of full synthetic.
I'm using synthetic blend on my 191263 mile 2AZ-FE, i4 04 Camry. It's leaking oil somewhere or just burning it off (engine known to burn oil), and i lose a quart of it every 3500 miles, when i used full synthetic, it burned off faster. now using some synthetic blend, and about 5 oz of oil additives, i don't lose a quart of synthetic oil as fast as i used to. Also, on the Mississippi Gulf Coast, we don't have Costco, nearest Costco is in the downtown part of New Orleans or head East for Mobile, Alabama. So Costco is somewhat not everywhere and within a short drive like you think it would be.
1
May 01, 2026 01:29 AM
225 Posts
Joined Aug 2025
CalmShoe2276May 01, 2026 01:29 AM
225 Posts
Good deal. Worse case I'll use in the mower.
May 01, 2026 01:38 AM
2,477 Posts
Joined Oct 2008
asukaMay 01, 2026 01:38 AM
2,477 Posts
This is good if you have an older engine with no turbocharger, supercharger, or timing chain.

But for most modern cars, get an API SQ rated full synthetic, if you plan on keeping it after the warranty ends. Proven to extend engine longevity.
1
1
May 01, 2026 06:03 AM
32 Posts
Joined Dec 2007
dbishop23May 01, 2026 06:03 AM
32 Posts
Good deal but full synthetic is better.
May 01, 2026 06:32 AM
1,104 Posts
Joined Apr 2014
mouthforwarMay 01, 2026 06:32 AM
1,104 Posts
$5 rebate (up to 3X) through Castrol: https://www.castrol.com/en_us/uni...tions.html

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May 01, 2026 10:40 AM
252 Posts
Joined Nov 2022
WthaHatchetMay 01, 2026 10:40 AM
252 Posts
Quote from asuka :
This is good if you have an older engine with no turbocharger, supercharger, or timing chain. But for most modern cars, get an API SQ rated full synthetic, if you plan on keeping it after the warranty ends. Proven to extend engine longevity.
It really doesn't improve engine life. Regular oil changes do. Sticking to a conventional change rate of every 3k miles or 5k for synthetic will be the thing that makes your engine last longer. I have a 3800series 1 v6 with 258k miles. Never had anything but conventional changes every 3k miles with new filter.
1

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