Castrol Syntec Blend

[vronline]

I was looking at the specs for CSB 10w-40, and if I'm reading the data sheets correctly it looks thicker than either the GTX or Syntec 10W-40's. I'm not sure how this could be since it's supposed to be a blend of these two oils, right?

Can someone please help me understand this?

 

[Triple_Se7en]

From what I've read here, Castrol buys it's vehicle oils on the open market. So the base oils & weights may periodically change.

 

[vronline]

It looks like the blend, at least in this particular weight, has about the same specs as the High Mileage oil.

 

[LarryL]

When you buy a synthetic blend, how do you know how much is synthetic and how much is conventional oil? If this oil is Syntec, is it really a GIII conventional oil blended with a GI or GII.

 

[vad]

Bruce381?

 

[AndyH]

quote:

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Originally posted by LarryL:
When you buy a synthetic blend, how do you know how much is synthetic and how much is conventional oil?

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That's the thing...you don't know. I wouldn't expect any more than 15% to be synthetic, based on posts I've read here on BITOG.

 

[clg305]

I think it is alittle more involved than just pouring in a little syntec and mixing it with alittle gtx if thts whats you are gettin at. Correct me if i'm wrong?

 

[Blue99]

quote:

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...I'm not sure how this could be since it's supposed to be a blend of these two oils, right?

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A finished motor oil is blended from one or more base oil viscosities. The add pack increases the final viscosity by a couple of points & then VI improvers are used to meet the final 100C viscosity target.

The Syntec Blend product line is blended from Grp II/II+ base oils with anywhere from 20-50% synthetic Grp III or higher base oils.

I believe the practice of mixing 2 finished motor oil formulatiuons together is called "dumbbell" blending and is not a common practice for the major brands of motor oil.

 

[JMG]

How do you know this information?

 

[Ray H]

Unfortunately for aware consumers, there's no Federal mandate on synthetic content in a synthetic blend oil. The blenders aren't very forthcoming for the most part, either, for "competitive reasons". (Translation: we're like mushrooms to them - they keep us in the dark and feed us crap.)