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Product Information

Product Details
Part No. 15A66C
Warranty Details (30 DAY REPLACEMENT IF DEFECTIVE)
Castrol GTX 5W-20 is a synthetic blend motor oil with a double-action formula proven to clean away the sludge that can block engine oilways (1) and help prevent new sludge formation. Sludge is a thick, tar like substance caused by severe driving conditions such as heavy traffic, poor fuel quality, harsh driving conditions and exceeding oil change intervals. Sludge can block your engine's vital oilways like cholesterol and if untreated, can rob an engine of its power and ultimately its life. (1) When tested in engines with a high level of sludge

Product Features:
  • Premium-quality base oils and anti-wear additives that help extend engine life
  • Superior protection against engine sludge
  • Advanced protection against viscosity and thermal breakdown
  • Superior protection against high-temperature deposits
  • Meets or exceeds the following specifications:
  • API SP/SN PLUS/SN/SM
  • ILSAC GF-6
  • Meets Ford WSS-M2C945-B1
  • Meets Ford WSS-M2C960-A1
Specifications
Container Size:
32 fl.oz

Oil Class:
Standard

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4.83 out of 5
833 Customer Reviews
98% of respondents would recommend this to a friend
Ratings Distribution
5 Stars
740
4 Stars
71
3 Stars
6
2 Stars
6
1 Star
10
Yes absolutelyOldies but goodies need the very bestORDER WAS DONE RIGHT !
Only the best for my classic muscle carGood productGood stuffMy only auto parts storeGood For Your Car
Pros
50
Reduces Wear
49
Runs Clean
36
Safe
35
Improves Vehicle Performance
1
Great Engine Running
Cons
6
None
2
Dirty
1
Doesn't Work
1
Cost
1
Deal
Best Uses
42
Car
37
Regular Use
23
Truck
10
RV
2
Quick Fix
Car/Motorcycle Describe yourself
31
Auto Enthusiast
25
Casual Driver
17
Mechanic
7
Truck Enthusiast
5
Competitive Driver
Most Liked Positive Review
Truck ran better
I switched from the oil in the yellow bottle that starts with the letter P and I tell you I think my truck is running better with this oil in it. It seem to reduce engine noise, feels more smooth. I know I had about 3-4k miles on the last oil change so dont know, either im seeing and hearing things or something changed.
Most Liked Negative Review
When Castrol was great..
Back in the 80s we had a commercial where a group of nerdy scientists in lab coats set up a bunch of 4 cylinder engines in a white laboratory, filled them with different brands of oil. They then ran the engines and then drained them of oil. They continued to run the engines until, one after another, they blew up. The engine that had Castrol in it continued to run long after the other's siezed up with the lab coat guys looking on astonished. Of course that's just a commercial but I was a little kid and that advertisement had more effect on me than some NASCAR driver with huge sideburns trying to sell me Pennzoil or another NASCAR driver with a mullet selling me Valvoline. In modern times nobody except Lucas talks about how it can save an engine, and all oil brands are pretty much generic and the same. Royal Purple goes out of its way to say how purple food coloring somehow makes their product superior, but it's just purple food coloring, there's nothing chemically different about thier oil. They even went so far as to claim in a few commercials that they use nanotechnology to formulate their oil. Wow! A form of technology that is currently science fiction because we haven't even gotten to that point? But they're already allegedly using microscopic robots in their oil!!! Amazing! That must be what the purple food coloring is! Little robots from Star Trek the Next Generation! They removed the zinc from all the oil a few years ago but, surprise surprise, you can buy an additive to put the zinc back in!!! I guess the real question is why did they take it out and why can you now buy an additive to put it back in? I still buy Castrol, more out of stupid brand loyalty than anything else, and the fact that it's usually on sale, but it certainly doesn't instill the confidence that it will out perform all other engine oils. And to be honest, probably never did, but it was great advertising!
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Displaying Reviews 1 - 5Back to Top

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how to remove item from cart
Verified Reply - Steve
Hi Marion, I'm glad to assist you! Go to your cart by double clicking the cart icon and then click the "Remove" button below the product details to delete the item from your cart.
Does this product contain methanol?
Verified Reply - Solomon
No, Diana, this Castrol GTX 10W-30 Conventional Motor Oil (Part # 15B400) does not contain methanol.
i need 5 qt of castrol --which one come with the zinc -im in altoona iowa ----do you stock it -price this is my question
Verified Reply - Solomon
Hi Phil, you can contact our Advance Auto Parts store to check the availability of this part by calling us at 1-877-ADVANCE (238-2623) and press 3 and one of our store representatives will gladly assist you. Please note that price of the items can vary from zone to zone as our prices are zonal based. Once you enter your Zip Code into the Advance Auto Part’s website you will see the accurate price for this product. For further assistance, please feel free to call us at: 1-877-ADVANCE (238-2623) or contact our "Live Chat" support and one of our representatives will gladly assist you with any questions or concerns you may have.
Can I use the Castrol GTX 20/50 conventional for a break-in oil if I add a good zinc additive. sbc 68 Camaro
Verified Reply - John the Car-Doc
No! This Castrol GTX 20W-50 Conventional Motor Oil (5 Quart Jug) - Part # 15984B is not compatible with the 1968 Chevrolet Camaro. The exact motor oil for your vehicle is currently unavailable online. I would suggest that you visit the nearest Advance Auto Parts store to check the availability of this part.
does this oil have a Mil spec?
Verified Reply - Solomon
Hi Slade, I'm glad to help you! This Castrol HD 30W Conventional Motor Oil (Part # 151B00) will exceed the engine protection requirements for Ford ESE-M2C153 G and F, GM 6085M, Chrysler MS-6395M. For more information, I would suggest that you contact the manufacturer directly at 1-888-CASTROL and they would be in a better position to help you.
Displaying Question & Answer 1-5

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