Shell HX5 15w40 formulation

Wow i did not expect that! Thanks a lot for the explanation. I guess what's appealing about a good 15w40 is low Noack as well as as high-ish HTHS and of course lower price as i don't really like waste of any kind. Usually i still buy a high end synthetic to have something with a low Noack as i believe this is important to the health of the engine but it sounds like there are other options. This oil seems more up to date compared to many others on the shelves that are only SL rated.
One last comment...

SN 15W40 oils like this are almost certainly Group II/III oils.

SL 15W40 oils are more likely to be original Group I oils. There's nothing wrong with these. I did 15W40 Quartz for Total back in the day & it sold consistently for years & years (but has probably been superseded now). Be selective in the EU if only because American Group II base oil imports are restricted to protect what's left of the European Group I refining industry (I think both Total & CEPSA are still in the game but a lot has closed down).
 
Okay, I'll have a go at answering your question but first I want to talk about guitars...

........

That said, both of the rejected oils would give better fuel economy & we really do need to think of the children...
Thank you, from guitars to oil to children, great to have you here.
Yes I’m thinking about petrol engines.

One more question if I may, which of those oils would be better to combat late onset oil control ring stickage? I’m thinking the 15W40 with it’s lower Noack.

BTW just sent you a PM about some energy research being carried out at my university that you may be interested in.
 
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SN 15W40 oils like this are almost certainly Group II/III oils.

SL 15W40 oils are more likely to be original Group I oils. There's nothing wrong with these. I did 15W40 Quartz for Total back in the day & it sold consistently for years & years (but has probably been superseded now). Be selective in the EU if only because American Group II base oil imports are restricted to protect what's left of the European Group I refining industry (I think both Total & CEPSA are still in the game but a lot has closed down).
Is a SL group I 15w40 as good as a modern SN version as far as Noack goes? Also, the API says that SN ensures full compatibility with E85 fuel, is there any problem running a SL lubricant in an engine burning the stuff? Wow, Quartz 5000 15w40 is still sold everywhere here!
 
Is a SL group I 15w40 as good as a modern SN version as far as Noack goes? Also, the API says that SN ensures full compatibility with E85 fuel, is there any problem running a SL lubricant in an engine burning the stuff? Wow, Quartz 5000 15w40 is still sold everywhere here!
As far as Noack goes, an SL Group I 15W40 will have more or less the same Noack as an SN Group II 15W40 but there are caveats.

A Group II oil will be inherently more oxidatively stable than a Group I one. Extreme & excessive oxidation leads to the drop out of the very heavy condensation reaction products collectively known as 'sludge'. In theory, you might need less ashless dispersant to get a Group II oil through the industry standard Sequence VG test. This in turn would result in a significant drop in Noack.

However as with all things oily, it's never quite as simple as that. Ashless dispersant is the go-to component for improving diesel piston cleaniness. As all ACEA oils are forced to be dual-function oils (ie are specced for BOTH gasoline & diesel), a reduction in ashless dispersant for gasoline duty might not translate to a reduction, once the diesel requirements are also taken into account.

On balance, my advice would be to go for an SN oil if it's on offer, even if there's no difference in Noack.
 
Thanks a lot. What is your opinion on synthetic 5w40 and semi-synthetic 10w40 oils ? I get that the 5w40 will be a better oil on all fronts compared to a "mineral" 15w40 and that there's nothing it won't do better but what about a modern A3/B4, SN 10w40 with some approvals? They're almost as cheap as the 15w40 are. From my perspective and as said by SR5 somewhere, mineral 15w40 = good, semi-synthetic 10w40 = better, synthetic 5w40 = best. What would be your pick? Also, would you fear house brand oils and spend the extra 5 or 10 bucks on a big name such as Total or Shell? As an exemple, a popular choice here is Tech9 sold at Leclerc stores, which is made be Avia.
 
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Thanks a lot. What is your opinion on synthetic 5w40 and semi-synthetic 10w40 oils ? I get that the 5w40 will be a better oil on all fronts compared to a "mineral" 15w40 and that there's nothing it won't do better but what about a modern A3/B4, SN 10w40 with some approvals? They're almost as cheap as the 15w40 are. From my perspective and as said by SR5 somewhere, mineral 15w40 = good, semi-synthetic 10w40 = better, synthetic 5w40 = best. What would be your pick? Also, would you fear house brand oils and spend the extra 5 or 10 bucks on a big name such as Total or Shell? As an exemple, a popular choice here is Tech9 sold at Leclerc stores, which is made be Avia.
Apologies for the late response. I got caught up in another thread & then managed to lock myself out of BiTOG.

It's actually a very tricky question to answer. I used to do a lot of what they call 'matrix blending'. This is when rather than develop one single oil, you develop a whole load of oils simultaneously. A typical commercial exercise might be to work up a Group I/III matrix which covers 10W30, 10W40, 15W40, 15W50 & 20W50 (plus mono grades) with one DI pack (at a fixed treat rate), one VII (at a variable treat rate) & several different base oil slates (for a big global program, 15 different base oil slates wouldn't be unusual!).

Of these oils, in order of my personal preference (excluding fuel economy), I'd rank the oils 15W40 first, followed by 20W50, 10W30, 10W40 with 15W50 last. I'd base my (non-scientific!) judgement on Noack, VII loading, heavy base oil content & the relative ease with which they get through the various engine tests I had to run.

Nowadays I'd probably try & integrate 5W20, 5W30 & 5W40 into the matrix (especially if it was Group II/III with no Group I permitted). It's a toss up but speaking personally, I'd favour a cheap SN Group II/III 15W40 over a full Group III 5W40.

Hope that helps...
 
No problem! Fantastic and helpful answer as always. In fact i used quite a bit of 10w40 i got on sale over the last year but before that i never paid much attention to these oils. For me it was always a 5 or a 15w40 but at some point i stopped using the group I SL 15w40 oils because at the time i started reading car forums and thought they were garbage. I hear a lot of people shouting all over the internet in the french car community that 10 and 15w40 are complete junk and just good enough for lawnmowers and i believed that before BITOG. I don't doubt that a group I oil will be a good lubricant and offer great protection but maybe not very stable over a long OCI and maybe not that good as far as engine cleanliness. I looked at the prices of this HX5 15w40 at stores around me and it only costs 13€ at some of them while HX7 10w40 is around 20€ and Helix Ultra 5w40 is around 30€.

Edit : This is not my engine but this is as clean as mine, virtually as clean as the day it left the assembly line. Often, these late 90s engines where serviced with only MB 229.3/5 synthetics 5w40. Of course these engines often covered a lot of miles way before SN and maybe a group III was the only way to achieve that. I wonder if with a modern SN group II/III 15w40, this level of cleanliness would be possible and if the additive package could compete.

33617033_1309001442566568_8996860847552724992_o.jpg
 
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No problem! Fantastic and helpful answer as always. In fact i used quite a bit of 10w40 i got on sale over the last year but before that i never paid much attention to these oils. For me it was always a 5 or a 15w40 but at some point i stopped using the group I SL 15w40 oils because at the time i started reading car forums and thought they were garbage. I hear a lot of people shouting all over the internet in the french car community that 10 and 15w40 are complete junk and just good enough for lawnmowers and i believed that before BITOG. I don't doubt that a group I oil will be a good lubricant and offer great protection but maybe not very stable over a long OCI and maybe not that good as far as engine cleanliness. I looked at the prices of this HX5 15w40 at stores around me and it only costs 13€ at some of them while HX7 10w40 is around 20€ and Helix Ultra 5w40 is around 30€.

Happy to help.
 
so if you want to know anything, ask ....
If I may good sir,

Previously we had Castrol GTX 15W40 conventional oil which, has since been replaced by GTX 15W40 UltraClean which Castrol now call “Synthetic Technology” so I assume it’s a semi-synthetic Group II and Group III.

Both old and new 15W40s were rated API SN/CF and ACEA A3/B3.

Castrol says the new GTX UltraClean “Provides 50% superior sludge protection compared to tough industry standards*“ and “*50% cleaner than the industry standard as measured in the API SN Seq. VG Sludge test”.

Is this a significant claim, or rather typical of most products?

From memory the old GTX was called “Modern Engine” and I *think* may have claimed something like 25% better than Seq. VG, but all the old spec sheets have been pulled from the web, so I cannot be sure on that.
 
If I may good sir,

Previously we had Castrol GTX 15W40 conventional oil which, has since been replaced by GTX 15W40 UltraClean which Castrol now call “Synthetic Technology” so I assume it’s a semi-synthetic Group II and Group III.

Both old and new 15W40s were rated API SN/CF and ACEA A3/B3.

Castrol says the new GTX UltraClean “Provides 50% superior sludge protection compared to tough industry standards*“ and “*50% cleaner than the industry standard as measured in the API SN Seq. VG Sludge test”.

Is this a significant claim, or rather typical of most products?

From memory the old GTX was called “Modern Engine” and I *think* may have claimed something like 25% better than Seq. VG, but all the old spec sheets have been pulled from the web, so I cannot be sure on that.

I see Castrol have started to ape the marketing language of Shell. Oh well, if you can't beat them etc....

You're right. GTX 15W40 is now very likely a Group II/III mix. Anything that's SN, almost by definition can't be Group I. This means the base oil system is extremely resistant to oxidation.

The venerable Sequence VG test has been around for the last two decades (think it may now be defunct as they ran out of parts?). There were virtually no changes to the test throughout its lifetime but when API SN was introduced, they made the test limits a teensy weensy bit more severe, upping the passing Average Engine Sludge (AES) from 7.8 min to 8.0 min.

There's always been a 'sludge' test in the API PCMO specs. It started with the Sequence V in API SC. This was followed by the VB, VC, VD, VE & the VG. Conventional wisdom is that these tests define how much ashless dispersant you need in an oil to keep sludge from agglomerating & dropping out of solution. It took me a while to suss out this is actually not the case. The VG is better viewed as just another oil oxidation test. If you prevent the oil from oxidizing during the 240 hours of the test, it won't ever drop out sludge. This you can achieve by piling in on antioxidants (not dispersant) or... by moving to a more stable base oil system... like a Group II/III mix!

I didn't myself do that much with Group IIs. For a long time, they were very much 'an American thing'. However, before I escaped the asylum, I played around with a superb Taiwanese Group II. I sort of asked myself the question, given that this stuff is so good, what's the lowest treat of DI I could get away with to pass basic API SL? It's too long ago to remember numbers, but I remember it was very low & what's more, even with the low treat of DI, I got a stellar Sequence VG result!

So back to your question. Once you make the transition from Group I to Group II, unless you're a complete idiot, it's virtually impossible to fail the VG & the AES should always be very close to a perfect 10 rating. Castrol's marketing language is simply reflecting this basic fact. I honestly can't figure out where they're getting their '50% better than industry standard' because 50% better than an AES of 8.0 is 12.0 & the rating scale stops at 10.0!

The bottom line is this stuff is good oil.

Now, about you & Ozzies everywhere switching over to 0W20 to help save the 'ickle children???
 
9s on the VG are a bit those Woodwork tests that you took at school, when you were 16. You got an 8.9 for writing your name (and spelling it correctly) at the top of the exam paper...
 
I see Castrol have started to ape the marketing language of Shell. Oh well, if you can't beat them etc....

So back to your question. Once you make the transition from Group I to Group II, unless you're a complete idiot, it's virtually impossible to fail the VG & the AES should always be very close to a perfect 10 rating. Castrol's marketing language is simply reflecting this basic fact. I honestly can't figure out where they're getting their '50% better than industry standard' because 50% better than an AES of 8.0 is 12.0 & the rating scale stops at 10.0!

The bottom line is this stuff is good oil.

Now, about you & Ozzies everywhere switching over to 0W20 to help save the 'ickle children???
Thanks Joe90, I mean SonofJoe, I mean SonofSonof, ..... can I just call you Number3 ? N3 for short.

I was just trying to understand their marketing speak, and if it translated to anything real. But I must admit I never realised how good a SN 15W40 was until you explained it to me. I did suspect it had some natural advantages given it was a traditional diesel HDEO grade.

Australia was all about 20W50 when I was growing up, then we moved to 15W40, and now more and more are using 5W30. Myself include, as per my recent thread


I can afford those two 5W30’s and the Dexos1-Gen2 oil is a good fuel economy oil. That’s why I asked you about them earlier, your reply was most helpful.

Group III 5W30 (presumably A3/B4) or Group II 15W40 A3/B3? For me, the 15W40 is the better lubricant. Reasons are lower Noack, less VII, marginally more ZDDP & possibly less ashless dispersant (not that big a deal for gas engines, more significant for diesels). Also Group IIs are 'greener' to produce than Group IIIs. Also I'm notoriously cheap!

Group III 5W30 full synthetic A3/B4 vs dexos1-Gen 2? For me, the A3/B4 oil wins BUT these two are so close, there's not a lot to differentiate them. I'd opt for the A3/B4 oil because it HASN'T been put through the US fuel economy tests. I don't like these tests because as often as not, they 'encourage' formulators to drop the oil's CCS viscosity to silly levels to cheat the test. Lower CCS means more VII & higher Noack. The A3/B4 oil might also have a higher ZDDP content (but not guaranteed) & a higher TBN.

That said, both of the rejected oils would give better fuel economy & we really do need to think of the children...

As for 0W20, well the price is the killer here.
I can get 15W40 regularly on sale at about $15 to $20 for 5L.
The full synthetic 5W30’s (either A3/B4 or D1-G2) are also regularly on sale for about $25 to $36 for 5L. Which I can stretch to.
But for 0W20 you are looking at $65 to $85 for 5L. These oils are rarely on sale, and when they are it’s not much off their regular full price.
Big difference between $20 and $80 when you still got to feed the children.
 
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there's also diminishing returns, SR5. With my new job being in the next city (just on the outskirts) I can manage 70 MPG (imperial) and then some on an A3/B4 oil, in winter...
 
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Thanks Joe90, I mean SonofJoe, I mean SonofSonof, ..... can I just call you Number3 ? N3 for short.

I was just trying to understand their marketing speak, and if it translated to anything real. But I must admit I never realised how good a SN 15W40 was until you explained it to me. I did suspect it had some natural advantages given it was a traditional diesel HDEO grade.

Australia was all about 20W50 when I was growing up, then we moved to 15W40, and now more and more are using 5W30. Myself include, as per my recent thread


I can afford those two 5W30’s and the Dexos1-Gen2 oil is a good fuel economy oil. That’s why I asked you about them earlier, your reply was most helpful.



As for 0W20, well the price is the killer here.
I can get 15W40 regularly on sale at about $15 to $20 for 5L.
The full synthetic 5W30’s (either A3/B4 or D1-G2) are also regularly on sale for about $25 to $36 for 5L. Which I can stretch to.
But for 0W20 you are looking at $65 to $85 for 5L. These oils are rarely on sale, and when they are it’s not much off their regular full price.
Big difference between $20 and $80 when you still got to feed the children.

I too started out as a 20W50 guy. The abomination that was my first car (an already knackered & rust-riven Austin 1100 that cost me £120!) called for 20W50 because the crankcase & gearbox shared the same oil. Thinking about it, I was only 'theoretically' a 20W50 guy. I was perpetually skint back then & rather than buy oil from a shop, I used to get a free supply of 'recycled oil' from my dad who (ahem..) 'liberated' it from where he worked! God knows what viscosity grade it was or whether it still contained any additives but it was free, so who cares??

The last time I bought oil, back in 2019, I paid £18.70 for a 5 litre can of Petronas Syntium 0W20 (a simple GF-5 full Group III). I remember thinking that's not too bad a price given that even the el cheap oils at the time were around the £15 a can mark.
 
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In my country, its possible to get Shell Helix Ultra on sale for the same price of HX-5 15W40 (which is never on sale). So I just use 5W40. There is also a worry about more heat generated from the 15W40, the climate over here is terribly hot and humid.
 
In my country, its possible to get Shell Helix Ultra on sale for the same price of HX-5 15W40 (which is never on sale). So I just use 5W40. There is also a worry about more heat generated from the 15W40, the climate over here is terribly hot and humid.
The heat generated by shear in the oil would be most significant at operating temperature and both are 40-grade oils. The winter rating would make no difference at all especially in Malaysia.
 
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