Redline 5w-20

[TooSlick]

Sir Winston,

It would be more proper to say it's proportional within a given product line; using the same basestock blends. For example, you can take the Mobil 1 or Amsoil products, look at their kinematic (low shear rate), viscosities @ 100C and closely estimate their HT/HS viscosities.

This case is particularly easy, since the 5w-20 and 10w-30 have the same viscosity index - and neither one is using any polymeric thickener. So their viscosity will be unaffected by shear rate and you have a simple temp/viscosity affect....

The other general trend is that narrow range multigrades, ie 5w-20/10w-30/15w-40/20w-50, will have greater HT/HS viscosities for a given kinematic viscosity @ 100C. The reason is that they simply have less polymeric thickener. When you test multigrades in a tapered bearing simulator, these long chain polymers align themselves in the direction of flow and the oil temporarily thins out.

For example, a synthetic 15w-40 with a 14.5 Cst viscosity @ 100C will have a HT/HS of about 4.3, vs a HT/HS of about 3.6 for an SAE 0w-40. (I just happened to pick that example

)

 

[bruce381]

I generally agree but the problem is that unless you have RL formula book you do not know what type or if any VII is used a guess is only a guess.
Bruce

 

[TooSlick]

Jay,

If the 10w-30 is indeed 3.5 Cp (which seems very reasonable), then there is NO WAY the 5w-20 is to 3.3 Cp. It's about 15% thinner than the 10w-30 in terms of kinematic viscosity @ 100C and the HT/HS will be proportional to that.

I certainly would not take your bet, given what I know about viscometrics of multigrade lubes.


Here's another simple way to look at this data - we used to call this Algebra before they started teaching that "Fuzzy Math"

"X"/3.3 = 3.5/3.8

Solving for "X" yields a 3.04 Cp for the 5w-20.

I think that Jason and Bulwnki should split the cost of the test.

I already know what the answer will be....

 

[jason07-1zzfe]

Yeah if that were true, GC would have a higher HTHS than it does, since it is much thicker @100C. M1 should have a slightly higher HTHS as well. It's not that simple as VI, 100C, and HTHS being the only factors.

 

[bulwnkl]

quote:

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Originally posted by TooSlick:
It would be more proper to say it's proportional within a given product line; using the same basestock blends.

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Can you see how different that statement is from the direction you started in this thread? The above is essentially what I was trying to point out to you when you first made the Amsoil-RedLine comparison. I'm sorry that was apparently unclear. Now go from there to 427Z06 and bruce381's posts and see where that takes you.

 

[TooSlick]

Just to add to the confusion, I called Dave at RL yesterday and had a nice 20 minute talk about a number of topics. He looked up the numbers and claims the 5w-20 is @ 3.3 Cp and the 5w-30/10w-30 are at 3.8 Cp.

So I'm done with this silly discussion....

TS

 

[buster]

Jason emailed me a spec sheet from 2003, which is more current then the 2002 one posted on the website.

5w/10w-30 - 3.5 HT/HS
5w-20 3.3 HT/HS

I simply don't know which are the correct numbers.

 

[buster]

quote:

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Michael,
The current HTHS viscosity is 3.8 cP for the 5W30 and the 10W30, it
is high compared to other products, but higher film strength is
certainly one advantage of our product.

Regards, Dave
Red Line Oil

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[TooSlick]

What matters is how well the stuff works in an actual application. Not how impressive it seems on paper....

TS

 

[Johnny]

BINGO!