Castrol 0w40 vs Mobil 1 0w40

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I tried looking up which is better of the two (shear stable, better at lubricating, etc) but could only find something from two years ago. Now that the GC is more available and been around for a little longer, I was hoping that people were to make some comments between two. I want to hear your thoughts.
 
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You're splitting hair. They both meet the same stringent mfg specs, and therefore offer the same level of performance, for all intents and purposes.
 
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Both are excellent. My suggestion is to try each in your car and see how they work. I suspect you won't notice much of a difference.
 
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For me it's Castrol. Up here when Castrol goes on sale (one retail outlet), all the grades will be on sale. I have never seen Mobil 1 0w40 on sale. So last time when Castrol Edge went on sale for $25 cdn / 5 litre jug I bought some. Now it's on for around $34 instead of the usual $53 cdn. Mobil 1 0w40 will be around $50 or so. Which one would you buy ?
 

OVERKILL

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Originally Posted By: 2KBMW
For me it's Castrol. Up here when Castrol goes on sale (one retail outlet), all the grades will be on sale. I have never seen Mobil 1 0w40 on sale. So last time when Castrol Edge went on sale for $25 cdn / 5 litre jug I bought some. Now it's on for around $34 instead of the usual $53 cdn. Mobil 1 0w40 will be around $50 or so. Which one would you buy ?
CT/Partsource has M1 on sale somewhat regularly FYI.
 
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Originally Posted By: route66mike
M1 0w-40 meets Nissan GT-R and Castrol doesn't. One upped.
I'm sure that has more to do with money exchanging hands than it does product performance. The GT-R oil spec is not even published, AFAIK...so it's not like someone could even submit an oil for approval.
 
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And to be fair, Mobil's exact wording is: Mobil 1 0W-40 synthetic motor oil meets or exceeds the requirements of: Nissan GT-R Semantics, but as we've discussed before, it's very deliberate.
 
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I tried the 0W-40 and didnt like the sluggish warm-ups, but there is no doubt in my mind of how stout these two oils are. That alone isnt the reason i wont use it, the lack of the API starburst is (warranty). My question (off topic and my apologies): What do you think of EDGE EP (FST) 5W-30 instead (5K mile oci)?
 
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Your new car warranty requires the use of an API starburst oil or it is invalid?
Originally Posted By: wemay
I tried the 0W-40 and didnt like the sluggish warm-ups, but there is no doubt in my mind of how stout these two oils are. That alone isnt the reason i wont use it, the lack of the API starburst is (warranty).
 
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Side note:trucking industry been using 15w40 since when?when dd serie 60 was born that was what in 1987?been driving for 20 year been in big rig for 21 year and in all that time the only thing boss checked was its api and is it 15w40.brand ?lol!bottle could be blank as long as officially that oil was api proper and irlt was 15w40 !that was it.even today ,truck mainly use 15w40.oh they comme out with fancier oil .like 10w30 (synblend for big rig)but often get 15w40 in a jiffy.im glad people like *w40 but brand does not much mather.
 
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kschachn, It recommends ILSAC GF-4 / SM / ACEA A5 and shows the Starburst in the owner's manual but i don't recall that it states the need for the starburst explicitly. The ILSAC is another hurdle. The FST has all of these covered. just-in-case
 
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Which one is better? Considering the specs isn't enough. There's in fact, no way to answer your question without a lot of time and money and would include some real world testing. And the difference would probably not be enough to bother with. Pick one if it meets your requirements, you're done. Pick one because you like the advertising, or the label on the bottle. The rest of what you do, and how you drive and where you live and park your car will be more important matters that you can deal with every day.
 
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Originally Posted By: wemay
kschachn, It recommends ILSAC GF-4 / SM / ACEA A5 and shows the Starburst in the owner's manual but i don't recall that it states the need for the starburst explicitly. The ILSAC is another hurdle. The FST has all of these covered. just-in-case
Actually, this sounds like the OP's language as well. And I commend the OP by not being afraid to run 0W-40! Although the manual does have language about thicker viscosity being required in high temps and "5W-40 conventional" being allowed for replenishment. LOL Not that even running 5W-30 guarantees warranty coverage anyway. A recent 2013(?) WRX owner at nasioc initially had his warranty denied and the oil changes were performed by the dealer! They were blaming him for not checking the oil (owner's manual states at every fill up), but SoA eventually decided to goodwill it after a couple of weeks or so. Hey, where's Pablo? I think he's been in shock at all of these recent WRX and STI failures. Sorry to ramble and go OT when 5W-30 isn't even the original question. smile So what's a better detergent/dispersant package for a 4 pot turbo pumping out over 300hp? The primarily calcium package of M1 or the lower calcium, higher magnesium package of the Castrol? More calcium? Or just flip a coin. popcorn
 
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I'm not sure what exactly one is best. I use the Castrol 0w40 oil. One thing does make me wonder about how good Castrol 0w40 is. Many people have positive reviews of GC 0w30 and many negative reviews of Castrol 5w40 and both oils are made for similar cars. Of course, it might not be exactly fair that I don't use M1, because I'm not always impressed with the UOA of their 5w30, and there have been a few unimpressive UOAs with 0w40.
 

Jteran5

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Originally Posted By: bluesubie
Originally Posted By: wemay
kschachn, It recommends ILSAC GF-4 / SM / ACEA A5 and shows the Starburst in the owner's manual but i don't recall that it states the need for the starburst explicitly. The ILSAC is another hurdle. The FST has all of these covered. just-in-case
Actually, this sounds like the OP's language as well. And I commend the OP by not being afraid to run 0W-40! Although the manual does have language about thicker viscosity being required in high temps and "5W-40 conventional" being allowed for replenishment. LOL Not that even running 5W-30 guarantees warranty coverage anyway. A recent 2013(?) WRX owner at nasioc initially had his warranty denied and the oil changes were performed by the dealer! They were blaming him for not checking the oil (owner's manual states at every fill up), but SoA eventually decided to goodwill it after a couple of weeks or so. Hey, where's Pablo? I think he's been in shock at all of these recent WRX and STI failures. Sorry to ramble and go OT when 5W-30 isn't even the original question. smile So what's a better detergent/dispersant package for a 4 pot turbo pumping out over 300hp? The primarily calcium package of M1 or the lower calcium, higher magnesium package of the Castrol? More calcium? Or just flip a coin. popcorn
Thanks for the praise. I didn't want to run a 30 weight because I know that they can shear fast if I drive my car hard (which I do). I just wanted to make sure that the engine is still being lubricated properly and protected at higher rpms. I went with a 0w40 as opposed to a 5w40 because even though I will never see 0 degrees Celsius where I am, I figure since it is targeted for lower Temps, then why would it hurt lol. I added a can of ceratec with my last oil change and again every 30k while and using mos2 every oil change in between. I will also add 2oz of redline break in oil at every oil change just for the ZDDP. I also use a bottle of redline si-1 on the last tank of gas before every oil change just to have nice and clean injectors. It couldn't hurt and I know that redline has one of the highest PEA counts, even more than chevron techron. I know that a lot of this is probably a little overboard but this is just pennies compared to the maintenance cost of an engine repair out of warranty (because I don't plan on keeping the car stock for long haha). On a side note, I would love to get my hands on Motul 0w40 but the cost is almost 3x the cost of Castrol / Mobil and I think they are very similar. Also to the person who asked if I prefer BP vs exxon, I do prefer BP and have use did at every fill and saved every receipt since I got the car at 6 miles (7100 as of today). I was so anal about the break-in of my car (my first ever new car) that I changed the oil at 100 miles and filled it with amsoil SAE30 (break-in oil) which I changed every 300 (three hundred) miles before my 1000 mile switch to Castrol 0w40. (4 oil changes at the 1000 mile mark).
 
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Jteran5

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Bluesubie, you wouldn't happen to be the same one from nasioc or iwsti (Dennis) would you? I forgot what you posted somewhere but if you're the same person, I picked up most of the things I'm doing because of you! (If not, please disregard)
 
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