0* cst for various oils

[JT1]

Hi, here are some 0c(32f) cst for various oils. I found these using a visc. calculator that uses the 40c and 100c cst ratings and then calculates your target temp.

RTS 5w40-457cst

Valv. Conv
5w30-314
10w30-382
10w40-543
SAE30-559
SAE20w-265

Valv. Synpower
5w30-284
10w30-332
0w20-216

Mobil 1
5w20-230

Mobil Clean 5k
5w30-311
10w30-383

 

[d00df00d]

A viscosity calculator that uses viscosities at 40º C and 100º C won't be very accurate at 0º C.

 

[Quattro Pete]

Originally Posted By: d00df00d
A viscosity calculator that uses viscosities at 40º C and 100º C won't be very accurate at 0º C.

I was thinking the same thing. These calculators have their limitations, but I guess it's a start.

 

[bepperb]

That correlates pretty well to my valvoline bottle shaking experiment this year.

At above 0, I couldn't tell which was which, VWB or Synpower 5-30. But the 10-40 was obvious.

At ten below, you could tell all three apart but the difference between the 30's was negligible.

Unfortunately, I didn't have a valvoline 20 weight available for shaking.

 

[JT1]

Originally Posted By: d00df00d
A viscosity calculator that uses viscosities at 40º C and 100º C won't be very accurate at 0º C.


Well then what temperature will it be accurate to, and what are you basing this claim off of?

 

[BobFout]

Visco calculators are generally accurate to freezing (they calculate VI from the 40C and 100C viscos), but not below freezing.

 

[JT1]

Well 0c isn't below freezing is it.

 

[Audi Junkie]

The calc can surely predict which oil is thicker or thinner just below freezing.

 

[Gary Allan]

Originally Posted By: JT1
Well 0c isn't below freezing is it.

Relax, JT ..I would assume that there's some inaccuracy that grows the further out you go, but I also imagine that the results will be close enough for comparative view.

 

[CATERHAM]

Originally Posted By: Gary Allan
Originally Posted By: JT1
Well 0c isn't below freezing is it.

Relax, JT ..I would assume that there's some inaccuracy that grows the further out you go, but I also imagine that the results will be close enough for comparative view.



+1

My understanding is that the Widman Calculator is accurate down to 0C and pretty good down to -10C. If you are comparing oils of similar base oil composition you can go lower than that if you're simply want to know relative comparisons.