Will a 20wt Oil have the same protection as a 30wt?

Shel_B

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Not a thick vs thin debate, just a simple question.

I have seen a number of XW-30 oils with an HT/HS of around 3.0, +/1 a tenth or two percent. Red Line, and I am told others, has a 5W-20 oil with an HT/HS of 3.0. Will a 20wt with that number offer the same protection as a 30wt with a similar HT/HS?
 
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Most would say that the 20 and 30 are just general categories in which the viscosity of the oil falls into whereas HTHS is a measure of actual protection.
 
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Not a thick vs thin debate, just a simple question.

I have seen a number of XW-30 oils with an HT/HS of around 3.0, +/1 a tenth or two percent. Red Line, and I am told others, has a 5W-20 oil with an HT/HS of 3.0. Will a 20wt with that number offer the same protection as a 30wt with a similar HT/HS?
A twenty weight with a hths of 3.0 is pretty stout and will have little to no VI so it's gonna be stable. These are found in boutique oils no found in Walmart and not under the 12.50 a qt or less price range. You aren't going to find many as a lot of otc 5w20 oils are around 2.6hths. They are economy oils,not performance oils. Personally I would put RL HP 0w20 or 5w20 against standard synthetic 5w30. Many times in fact Redline tells users to go down a weight as their oils are on the thicker end of the weight scale.
 
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RedLine notes a higher oil film in the bearings compared to similar oil viscosities. i am not a pro but do believe real synthetics like redline are better if you dont mind the $$. depending on your ambient temps a cheeper 5 or even 10W 30 fake synthetic is prolly enough protection for most applications IMO. i dont believe in or use any xxW20 oils in my Pa climate + my 2001 audi TT 225Q with enhanced output gets Redline only as it has a small 4.25 qt sump. i found that with thicker Redline 15w50 in the summer shows more vacuum + less consumption on my lo mile but "loose" 1.8T that boosts a bit over 25LB!!
 
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Not sure about 5w20 but I heard somewhere that 0w20 and now 0w16 are very shear stable.
 

OVERKILL

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Not a thick vs thin debate, just a simple question.

I have seen a number of XW-30 oils with an HT/HS of around 3.0, +/1 a tenth or two percent. Red Line, and I am told others, has a 5W-20 oil with an HT/HS of 3.0. Will a 20wt with that number offer the same protection as a 30wt with a similar HT/HS?
Short answer: yes. KV isn't measured under shear, while HTHS is. Of course, as you know, there are many Euro 5w-30 and 0w-30's with an HTHS of 3.5cP or higher, so the higher HTHS thing isn't exclusive to boutiques in general, it's just not pursued with xW-20's because those oils are historically geared towards economy and resource conserving type operation and the 2.6cP HTHS range is in-line with that.

Redline's 0w-20 has a VI of 172, so it has plenty of VII in it despite its 2.9cP HTHS. The 5w-20 with its VI of 147 probably has little to none.

It all comes down to what the blender is targeting.
 
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Not a thick vs thin debate, just a simple question.

I have seen a number of XW-30 oils with an HT/HS of around 3.0, +/1 a tenth or two percent. Red Line, and I am told others, has a 5W-20 oil with an HT/HS of 3.0. Will a 20wt with that number offer the same protection as a 30wt with a similar HT/HS?
No never
 
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Depends on the engineering of the engine more than the oil. I'd say yes if the engine's engineering is catered to have the oil work less hard and not breech moft for part separation. Good engineering on the engines side and its tuning as well can greatly help in giving the oil an easier job separating the parts and allow it to have great protection. It's only when the engineering isn't enough that you have to bump up a grade or come up with a very stringent spec because of how much power it's gonna make or how they think its gonna get treated in the real world.

I don't fully trust when the same engine platform as before is forced to go down a grade the next year for economy but I trust when a brand new redesigned engine platform is made to run on a specified grade. But even then Toyota released the new 3 cyl Yaris hybrid in Europe using their latest high efficiency architecture and I made a post about it showing everything from 0w-8 to 5w-30 in its manual so take it FWIW.
 
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My initial instinct is to go with 30 if I want a thick(er) oil as oppose to a stout 20.
High HTHS 20? Is that a thick thin oil for a very niche market?

In general, any odd or a specialty product will be pricy!
I'm sure some ladies would love to have a high heel hiking shoes.

Curious, does this oil meet SAE otherwise? iirc, KVs have a min/max limit/range but for HTHS, only a min is specified. No?
 
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A poor horse repeatedly beaten here. Everything is fine until a rare event, maybe not so rare that you need the extra margin of protection, like an extremely hot day in a major traffic jam, a thermostat going bad, a coolant leak, etc. Then the extra "thickness" provided by a 30 grade vs. a 20 grade comes into play.
 
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Not a thick vs thin debate, just a simple question.

I have seen a number of XW-30 oils with an HT/HS of around 3.0, +/1 a tenth or two percent. Red Line, and I am told others, has a 5W-20 oil with an HT/HS of 3.0. Will a 20wt with that number offer the same protection as a 30wt with a similar HT/HS?

Yes, if the additive package has comparable efficiency.
 
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