What temp does the "W" start?

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At what temp does the "w" effect kick in with most typical 5w-30 and 10w-30 oils? I know its not linear, and I am just looking for a general point where it happens. Around 40 degrees? Maybe 32?
 
CCS is measured at -25 for 10wXX, -30 for 5wXX & -35 for 0wXX.
MRV is measured at -30 for 10wXX, -35 for 5wXX & -40 for 0wXX.

Not really sure what you mean by effect.

Code:


10w30 10w30 5w30 5w30 0w30

Syn Syn Syn

cSt@40 67.7 64.3 62.3 63.9 61.9

cSt@100 10.4 10.5 10.7 11.0 11.2

VI 141 153 164 166 177

-35 26285.39 18177.93 13518.98 13375.55 10088.59

-30 13629.08 9820.37 7557.92 7518.97 5855.20

-25 7462.39 5577.42 4425.56 4423.83 3544.69

-20 4291.04 3313.63 2701.94 2712.10 2229.38

-15 2578.77 2050.36 1713.10 1725.73 1451.44

-10 1612.72 1316.20 1123.93 1135.75 975.07

-5 1045.56 873.52 760.62 770.70 673.99

0 700.33 597.51 529.47 537.73 478.13

5 483.18 420.08 378.14 384.81 347.31

10 342.45 302.81 276.45 281.81 257.79

15 248.72 223.30 206.46 210.78 195.16

20 184.71 168.12 157.22 160.72 150.45

25 139.99 129.00 121.88 124.72 117.92

30 108.09 100.71 96.04 98.37 93.84

35 84.88 79.89 76.82 78.75 75.73

40 67.70 64.30 62.30 63.90 61.90

45 54.77 52.45 51.16 52.51 51.20

50 44.89 43.31 42.51 43.65 42.82

55 37.24 36.17 35.70 36.67 36.17

60 31.24 30.52 30.28 31.11 30.84

65 26.47 26.01 25.92 26.63 26.52

70 22.64 22.36 22.37 22.99 22.99

75 19.53 19.37 19.46 20.00 20.08

80 16.98 16.92 17.05 17.53 17.65

85 14.88 14.88 15.04 15.46 15.62

90 13.12 13.17 13.35 13.73 13.91

95 11.65 11.73 11.92 12.25 12.45

100 10.40 10.50 10.70 11.00 11.20
 
Originally Posted By: gfh77665
At what temp does the "w" effect kick in with most typical 5w-30 and 10w-30 oils?

Kick in? It's not an on/off switch. The "W" defines an entire curve.
 
Originally Posted By: ARCOgraphite
Does not the VI defines the curve.

VI is just a calculated parameter based on 40C and 100C viscosity.
 
Pete is correct about VI above.

Wax, base oil viscosity, and the interactions between wax and polymers (PPDs and VMs) play a much, much more important role at below-zero temperatures than just the VI of the oil. It is much more about structure and stacking interactions than at higher temperature.
 
Originally Posted By: sasha
32F or 0c. pretty much freezing point of water.

Not really. I heard that years ago but then found out that the sample point is much lower and not at the same temp for 0W/5W/10W/15W/20W.
 
Originally Posted By: cp3

Not really sure what you mean by effect.


The point when the oil begins to thin substantially, as the temp drops.
 
Originally Posted By: gfh77665
Originally Posted By: cp3

Not really sure what you mean by effect.


The point when the oil begins to thin substantially, as the temp drops.

I think you meant 'thicken', not 'thin'.
smile.gif
 
The "w" stands for winter, and multi-visc oils try to stay THIN as the temps drop. Where (what temp) is that point where that effect happens? That is what am referring to.
 
Originally Posted By: jake88
Pete is correct about VI above.

Wax, base oil viscosity, and the interactions between wax and polymers (PPDs and VMs) play a much, much more important role at below-zero temperatures than just the VI of the oil. It is much more about structure and stacking interactions than at higher temperature.
SAE (API)defined three std data points where Kv is measured. How are you defining the temp v. Viscoity curve? Wideman viscosity estimator algorithm?
The OP must be concerned about the kneepoint moving toward gellation - or they are still confused thinking that multivis oil gets "thinner"* in dropping winter temps at some "magic" point - which is incorrect thought.
* inappropriate use of a linear dimension
 
Last edited:
Originally Posted By: gfh77665
The "w" stands for winter, and multi-visc oils try to stay THIN as the temps drop. Where (what temp) is that point where that effect happens? That is what am referring to.


No.

While the "W" designation does denote Winter, it doesn't mean the oil "gets thin".

What it means is simply that the oil RESISTS thickening more than a straight-weight oil like SAE 30 for example.

The CCS and MRV values were posted earlier, and they are what define the "W" rating. The lower the MRV and CCS numbers, the less steep the viscosity slope going from cold to hot; the less change there is between the (thicker) cold viscosity and the oil's hot viscosity.

On top of that, there is VI, which is the viscosity index, which gives you the curve/slope for the oil's viscosity between 40C and 100C. This can be extrapolated in either direction, however it doesn't give you accurate information below 0C. This is where MRV and CCS are valuable.
 
Originally Posted By: gfh77665
The "w" stands for winter, and multi-visc oils try to stay THIN as the temps drop. Where (what temp) is that point where that effect happens? That is what am referring to.

Basic principles:

1. ALL oils thicken as the temperature drops.

2. Multi-grade oils thicken a little less than single grade oils, but they still thicken. It's a basic law of physics (or is it chemistry?).

3. There is no magic "point" where all of a sudden the "W" comes into effect. A multi-grade oil resists thickening better than single grade oil in general, and that applies to the entire temperature range, not just some arbitrary single point.
 
Originally Posted By: Quattro Pete
Originally Posted By: gfh77665
The "w" stands for winter, and multi-visc oils try to stay THIN as the temps drop. Where (what temp) is that point where that effect happens? That is what am referring to.

Basic principles:

1. ALL oils thicken as the temperature drops.

2. Multi-grade oils thicken a little less than single grade oils, but they still thicken. It's a basic law of physics (or is it chemistry?).

3. There is no magic "point" where all of a sudden the "W" comes into effect. A multi-grade oil resists thickening better than single grade oil in general, and that applies to the entire temperature range, not just some arbitrary single point.

The "W" might not even reflect performance at temperatures above freezing. It's probably going to need pour point depressants to get good cold temp performance. I'm thinking it might be possible to make an almost identical oil as a 30 wt that operates almost the same as a 5W-30 above freezing temps.
 
Originally Posted By: cp3
CCS is measured at -25 for 10wXX, -30 for 5wXX & -35 for 0wXX.
MRV is measured at -30 for 10wXX, -35 for 5wXX & -40 for 0wXX.

Not really sure what you mean by effect.

Code:


10w30 10w30 5w30 5w30 0w30

Syn Syn Syn

cSt@40 67.7 64.3 62.3 63.9 61.9

cSt@100 10.4 10.5 10.7 11.0 11.2

VI 141 153 164 166 177

-35 26285.39 18177.93 13518.98 13375.55 10088.59

-30 13629.08 9820.37 7557.92 7518.97 5855.20

-25 7462.39 5577.42 4425.56 4423.83 3544.69

-20 4291.04 3313.63 2701.94 2712.10 2229.38

-15 2578.77 2050.36 1713.10 1725.73 1451.44

-10 1612.72 1316.20 1123.93 1135.75 975.07

-5 1045.56 873.52 760.62 770.70 673.99

0 700.33 597.51 529.47 537.73 478.13

5 483.18 420.08 378.14 384.81 347.31

10 342.45 302.81 276.45 281.81 257.79

15 248.72 223.30 206.46 210.78 195.16

20 184.71 168.12 157.22 160.72 150.45

25 139.99 129.00 121.88 124.72 117.92

30 108.09 100.71 96.04 98.37 93.84

35 84.88 79.89 76.82 78.75 75.73

40 67.70 64.30 62.30 63.90 61.90

45 54.77 52.45 51.16 52.51 51.20

50 44.89 43.31 42.51 43.65 42.82

55 37.24 36.17 35.70 36.67 36.17

60 31.24 30.52 30.28 31.11 30.84

65 26.47 26.01 25.92 26.63 26.52

70 22.64 22.36 22.37 22.99 22.99

75 19.53 19.37 19.46 20.00 20.08

80 16.98 16.92 17.05 17.53 17.65

85 14.88 14.88 15.04 15.46 15.62

90 13.12 13.17 13.35 13.73 13.91

95 11.65 11.73 11.92 12.25 12.45

100 10.40 10.50 10.70 11.00 11.20






Nice chart...been looking for one, where did you find it?
 
Originally Posted By: gfh77665
At what temp does the "w" effect kick in with most typical 5w-30 and 10w-30 oils? I know its not linear, and I am just looking for a general point where it happens. Around 40 degrees? Maybe 32?


One way to get a general answer is look at a manufacturer's oil viscosity recommendation chart. If both weights are appropriate just look at what low temp the 10w30 goes down to. Most I've seen recommend 10w30 from 0c all the way down to -20c. Below that 5w30 is recommended.

So the cutoff point to where a thinner startup 5w30 oil is usually recommended is anywhere from 0c down to -20c.
 
Whats interesting is the start up viscosity at 10-20c or so which would be my garage temp in spring.

The 0w is significantly thinner so would lubricate faster.
 
Originally Posted By: OVERKILL
Originally Posted By: gfh77665
The "w" stands for winter, and multi-visc oils try to stay THIN as the temps drop. Where (what temp) is that point where that effect happens? That is what am referring to.


No.

While the "W" designation does denote Winter, it doesn't mean the oil "gets thin".

What it means is simply that the oil RESISTS thickening more than a straight-weight oil like SAE 30 for example.



OK then! "At what temp does the oil RESISTS thickening more than a straight-weight oil"? Can anyone tell me?

Yes, I understand the viscosity principles quite well. I am sorry a seemingly simple question has become SO complex due to semantics.

I guess a simple C or F degree answer was asking too much...
 
Originally Posted By: Brule

One way to get a general answer is look at a manufacturer's oil viscosity recommendation chart. If both weights are appropriate just look at what low temp the 10w30 goes down to. Most I've seen recommend 10w30 from 0c all the way down to -20c. Below that 5w30 is recommended.

So the cutoff point to where a thinner startup 5w30 oil is usually recommended is anywhere from 0c down to -20c.


Best answer yet, thank you.
 
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