Slickdeals is community-supported.  We may get paid by brands for deals, including promoted items.
Heads up, this deal has expired. Want to create a deal alert for this item?
expiredphoinix | Staff posted Apr 02, 2026 07:27 PM
expiredphoinix | Staff posted Apr 02, 2026 07:27 PM

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

w/ S&S

$19

$25

24% off
Amazon
15 Comments 4,880 Views
Visit Amazon
Good Deal
Save
Share
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 SubZero5 | Staff
  • About this Deal:
    • This offer matches the recent FP 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 ratings.
  • 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 SubZero5 | Staff
  • About this Deal:
    • This offer matches the recent FP 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 ratings.
  • About this Store:

Original Post

Written by phoinix | Staff

Community Voting

Deal Score
+35
Good Deal
Visit Amazon

Leave a Comment

Unregistered (You)

15 Comments

Sign up for a Slickdeals account to remove this ad.

Apr 02, 2026 07:54 PM
2,372 Posts
Joined Oct 2008

This comment has been rated as unhelpful by Slickdeals users.

Apr 02, 2026 08:05 PM
21,746 Posts
Joined Nov 2007
Buckeyefan 1Apr 02, 2026 08:05 PM
21,746 Posts

Our community has rated this post as helpful. If you agree, why not thank Buckeyefan 1

This is group 3, which is a synthetic blend in most other countries. If you want true synthetic, get a group 4 oil. European spec is always group 4.
Last edited by Buckeyefan 1 April 2, 2026 at 01:10 PM.
1
1
Apr 02, 2026 09:25 PM
2,156 Posts
Joined Jul 2008
kfunk7Apr 02, 2026 09:25 PM
2,156 Posts
Quote from Buckeyefan 1 :
This is group 3, which is a synthetic blend in most other countries. If you want true synthetic, get a group 4 oil. European spec is always group 4.
It is indeed a group 3 oil.
Apr 02, 2026 09:36 PM
1,847 Posts
Joined Jun 2010
Wolf1eApr 02, 2026 09:36 PM
1,847 Posts
Quote from asuka :
API SP for $19 is not a good deal anymore. Pay the extra few bucks and get an API SQ oil.

I will never again run below SQ on any car with a turbo and/or timing chain. The data shows it is going to add longevity.

I am totally confident enough to say I have bought my last jug of Rotella T6 even.
Uhh..API? Sq? @_@ 😅
2
Apr 02, 2026 09:49 PM
2,277 Posts
Joined Jun 2013
koge811Apr 02, 2026 09:49 PM
2,277 Posts
im just going to ignore manufactures recommendation for 0-20 and use 5-30 instead its getting too thin and not protecting the bearings.
Apr 02, 2026 10:03 PM
2,947 Posts
Joined May 2018
TimlessApr 02, 2026 10:03 PM
2,947 Posts
Quote from koge811 :
im just going to ignore manufactures recommendation for 0-20 and use 5-30 instead its getting too thin and not protecting the bearings.
Straight 40 is what real men run.
1
1
Apr 02, 2026 10:03 PM
2,947 Posts
Joined May 2018
TimlessApr 02, 2026 10:03 PM
2,947 Posts
Quote from asuka :
API SP for $19 is not a good deal anymore. Pay the extra few bucks and get an API SQ oil.

I will never again run below SQ on any car with a turbo and/or timing chain. The data shows it is going to add longevity.

I am totally confident enough to say I have bought my last jug of Rotella T6 even.
Where is this data?
1

Sign up for a Slickdeals account to remove this ad.

Apr 03, 2026 12:17 AM
219 Posts
Joined Jun 2011
colklink77Apr 03, 2026 12:17 AM
219 Posts

Our community has rated this post as helpful. If you agree, why not thank colklink77

Quote from asuka :
API SP for $19 is not a good deal anymore. Pay the extra few bucks and get an API SQ oil.

I will never again run below SQ on any car with a turbo and/or timing chain. The data shows it is going to add longevity.

I am totally confident enough to say I have bought my last jug of Rotella T6 even.
I don't think you will add any appreciable wear to a regular port injection engine with a timing chain by running this oil. You may be thinking of increased timing chain wear from low speed pre ignition in turbocharged direct injection engines.
2
Apr 03, 2026 04:37 AM
5,763 Posts
Joined Jul 2003
BoomSchtickApr 03, 2026 04:37 AM
5,763 Posts
The four pack 5-quart from Costco is $17.50 each.
Apr 03, 2026 06:40 AM
1,539 Posts
Joined Oct 2016
LaughinGassApr 03, 2026 06:40 AM
1,539 Posts
Quote from asuka :
API SP for $19 is not a good deal anymore. Pay the extra few bucks and get an API SQ oil.

I will never again run below SQ on any car with a turbo and/or timing chain. The data shows it is going to add longevity.

I am totally confident enough to say I have bought my last jug of Rotella T6 even.
You post this in multiple oil deals. IDK why. "The data" (doesn't cite sources).
I've run several cars with timing chains north of 200k miles, using Super Tech oil changed every 10-15k miles. I have yet to ever come across a vehicle with timing chain (or any oil related) problems. Timing chains have been around a long time...longer than this oil.
Apr 03, 2026 03:58 PM
1,998 Posts
Joined Nov 2010
testshootApr 03, 2026 03:58 PM
1,998 Posts
Quote from LaughinGass :
You post this in multiple oil deals. IDK why. "The data" (doesn't cite sources).I've run several cars with timing chains north of 200k miles, using Super Tech oil changed every 10-15k miles. I have yet to ever come across a vehicle with timing chain (or any oil related) problems. Timing chains have been around a long time...longer than this oil.
Motor Oil Geek just had a video of a Ford engine with timing chain that had 500k miles running conventional oil. Only issue was some stuck piston rings. Restore and Protect took care of them.
Apr 03, 2026 05:51 PM
391 Posts
Joined Sep 2017
limocadApr 03, 2026 05:51 PM
391 Posts
Quote from koge811 :
im just going to ignore manufactures recommendation for 0-20 and use 5-30 instead its getting too thin and not protecting the bearings.

Modern engines have tight tolerances and will not expand over time unlike older engines. Thicker oil will starve the engine of the oil it needs and cause premature failure and also give you lower MPG. Stay with manufacturer recommended oil weights. But it's your car ultimately.
Apr 03, 2026 05:58 PM
10,825 Posts
Joined Nov 2010
youra6Apr 03, 2026 05:58 PM
10,825 Posts
Quote from limocad :

Modern engines have tight tolerances and will not expand over time unlike older engines. Thicker oil will starve the engine of the oil it needs and cause premature failure and also give you lower MPG. Stay with manufacturer recommended oil weights. But it's your car ultimately.
So many people think they know better than the engineers who made their cars.
Apr 03, 2026 07:25 PM
1,065 Posts
Joined May 2021
JollyReward108Apr 03, 2026 07:25 PM
1,065 Posts
Once again we get screwed on the price, says $23.96

Sign up for a Slickdeals account to remove this ad.

Apr 03, 2026 11:28 PM
1 Posts
Joined Apr 2022
OliveJuice876Apr 03, 2026 11:28 PM
1 Posts
Yeah, I always use this, more about changing on time. But what do I know? 2004 fore runner with 347,000 miles.

Leave a Comment

Unregistered (You)

Popular Deals

Trending Deals