Helix 15w-40 vs GTX 15w-40

[B320i]

Originally Posted By: SR5
Originally Posted By: SonofJoe

a 15W30 with a 3.5 HTHS and virtually no VII.

That sounds like a great oil, I would use it.

If its A3/B3, I'll chuck a "Me too!" in there for good measure.

While I'm here, maybe I should look into a 20w-40? *Ducks and runs*

 

[SR5]

Originally Posted By: SonofJoe

Both the GTX & HX5 15W40s will probably be very similar in their basic structure; Group II with a smidge of Group III, 22 SSI OCP VII (Lz 7077), a nothing special DI delivering 8-ish TBN and 800 - 1000ppm of Phos.


Originally Posted By: SonofJoe

15W40 oils, .... Now that they are primarily based on Group II, they are even better. You get good oxidation stability, 8 TBN min, a goodly amount of Zinc, great film strength, low wear and, most importantly, you get lowish Noack volatility.

The other thing I might add is that because 15W40 oils are as often as not formulated as a matrix (rather than individually), they tend to carry the treat rate of DI needed for the more problematic 10W40 grade. As such, most 15W40s benefit from being over-formulated.


All this makes me wonder how much "better" a semi-synthetic 10W40 (SN & A3/B4) is from a conventional 15W50 (SN & A3/B3) ? Apart from TBN differences (B4 > 10), I always assumed that the 10W40 semi-synthetic was much more advanced, it was certainly always priced more.

But now that I hear about this development matrix, the problematic 10W40 grade, and previously you have said that a semi-synthetic can be either a Group 1 & Group 3 mix or a Group 2 & Group 3 mix, so a semi may still contain Group 1. Sure the semi has better cold starting (10W) but that means nothing in Australia, where 20W50 will work year round.

It all makes me think the two oils (10W40 & 15W40) are closer than I first believed and that I may be better off buying the cheaper 15W40.

Apart from a bit more TBN and a bit more cold starting, does a 10W40 semi-synthetic offer me any more advantages over a 15W40 Group 2 mineral oil ?

 

[SonofJoe]

SR5,

Again, excellent and penetrating questions that all motorists should be asking!

If you're driving a gasoline engined car in a hot climate, and the choice is between a 10W40 semi-synthetic SN/A3/B4 and a 15W40 Group II based SN/A3/B3, then I would opt for the 15W40. The reasons I would go this way are lower Noack (people should IMO never underestimate just how important low Noack is to the long term health of an engine!), lower VII polymer loading, higher film strength and importantly (if you're a tightwad like me!) lower cost. There is no OCI advantage for the 10W40 (OEM recommendations are the same regardless of oil quality) and the FE differences between the two oils are negligible.

One last thing. Just because the 15W40 is labelled A3/B3, it doesn't mean it's not A3/B4 quality. The lower level of VII and higher level of heavy 500N base oil in the 15W40 generally go down well on the VW TDi test (which differenciates B3 & B4). However oil companies see it as important not to 'over-claim' for the cheaper oil so they will label it as A3/B3 even if in reality it's A3/B4.

Hope this helps.

 

[SR5]

Hey Joe,

That's excellent, thank you very much for the comprehensive reply.

I've been thinking more and more that I should either go full synthetic or full Group 2 mineral and avoid the in-between semi-synthetics. It looks to me like the Group 2 mineral oils have come a long way, but they are still sold as the base level product. I also think that the heavy grades sit well on Group 2 mineral oils, like you said it helps keep the Noack down. Cold climates and thin oils are of course completely different, and natural synthetic territory.

I've used GTX 15W40 before without problem. In reality it's probably all I need and very easy on the pocket.

 

[KL31]

[censored] SR5, I've seen 15W40 here sell at $60 a few times for.... 20L! Would definitely be a cheap option if it runs well in your car!

 

[SR5]

Originally Posted By: KL31
[censored] SR5, I've seen 15W40 here sell at $60 a few times for.... 20L! Would definitely be a cheap option if it runs well in your car!

Yeah, except I've got 30L of full synthetic and 15L of semi-synthetic to work through first.

And that's after resisting you tempting me with, what was it, Castrol Edge 5W30 A3/B4 at $25 for 5L ?
That's a dream oil at a dream price. It's BMW LL-01 and MB 229.5, with regular price of $70.

 

[SR5]

Originally Posted By: SR5
At Repco (to 15 Jan), Castrol GTX 15W40 (API SN and ACEA A3/B3) is on sale for $18 for 5L (50% OFF ). Everyday price is $36 for 5L


I just went past KMart today, the everyday price for Shell Helix HX5 15W40 is $26 for 5L.

 

[SonofJoe]

Ouch! £15.75 ($26) for a 5 litre can of mineral 15W40. Too high!

Asian Group II base oil was costing about $US 0.5/litre in December 2016. Do the maths!

 

[SR5]

You do the maths on bottled water that everybody drinks nowadays. It was filtered, treated and free from the tap last time I checked.

With oil, us poor consumers need to keep you prestigious oil industry workers living in the style to which you have become accustomed. How are those gold plated taps in your bathroom ?

 

[Jetronic]

tap water hasn't been nearly free since a long time now

 

[SR5]

Originally Posted By: Jetronic
tap water hasn't been nearly free since a long time now

Get a rain water tank like half of Oz, they haven't taxed the stuff falling from the sky yet. Distilled and purified by mother nature.

 

[SR5]

At SuperCheapAuto (SCA) in Australia, 1-12 February 2017.

Shell Helix HX5 15W-40 (SN, A3/B3) mineral
40% Off, $18 for 5L

 

[Ether]

Could i use an oil with this spec in a gasoline Engine ACEA E7/B4/B3/A3 API CI-4, or would this be suitable for just Diesel Engines

 

[SR5]

Originally Posted By: Ether
Could i use an oil with this spec in a gasoline Engine ACEA E7/B4/B3/A3 API CI-4, or would this be suitable for just Diesel Engines


If you have a petrol engine that spec's A3/B3 then Yes you can use this oil as it is an A3/B3 oil. I have only used it in petrol applications myself. But it would also be suitable for a light duty diesel that spec' s A3/B3 as well.

 

[Ether]

Great,thankyou

 

[SR5]

Originally Posted By: Ether
Great,thankyou

No worries, not everybody drives a car that needs a full synthetic 0W-40 and a $100 to $200 dealer oil change. For us mortals, a good 15W-40 SN/A3/B3 mineral oil can do the job. As long as very cold starting isn't an issue, below -15C say.

I worry a little about light mineral oils like a 5W20, but not heavy mineral oils like this 15W40. Very robust stuff.

 

[Garak]

Originally Posted By: Ether
Could i use an oil with this spec in a gasoline Engine ACEA E7/B4/B3/A3 API CI-4, or would this be suitable for just Diesel Engines

Look at my signature. I use an CJ-4/SM E7, E9 oil in my gasser, on a continent where all are afraid of thick oils.

 

[slybunda]

If your specced for 15w40 cant you use 5w40 fully too?

 

[SR5]

Originally Posted By: slybunda
If your specced for 15w40 cant you use 5w40 fully too?


Can you use a 5W40 synthetic instead of a 15W40 mineral?

Well I do, as my car OM says use a Euro A3 rated 15W-40 oil (which is only a mineral oil here), and I have used both 5W-40 and 0W-40 full synthetic oils (both Euro A3 rated) without concern. But, they both meet the Euro A3 rating.

If my vehicle called for a 15W-40 HDEO with API CJ-4 rating, then no I would not be happy to use a A3 oil in it's place in either 15W40 or 5W40 flavours.

It's important to match (or exceed for older cars) the oils spec called for.

But right now I'm using Valvoline SynPower 0W40, and previously I have used GTX 15W40, in the same car. All good.

 

[B320i]

Originally Posted By: slybunda
If your specced for 15w40 cant you use 5w40 fully too?

Yes, I've done this in the past.

Fact is, in Australia, oil costs a small fortune. A simple DIY synthetic oil change costs twice what I pay to fill the car with 98RON petrol.

Mineral oil in Australia is cheap, abundant and carries certifications (however basic) that surpass the car's specification in 1993* rather easily.

* For reference, CCMC-G5 rated oil with API-SG rating. CCMC-G5 was superseded by ACEA A3/B3 (or B4) in the late 1990s, and we're up to API-SN oils now.