GC 0W-30 Low Temp performance

[novadude]

From Castrols data sheet, I have found the following:

Low Temperature (ºC)
Pumping Viscosity, cP max
ASTM D-4684 60000@-40

Is it just me, or is that number awfully high for a 0W-30?

Note that GM 6094M calls for a max cP of 30,000 @ -40. What gives?

 

[bruce381]

60,000 is the MAX a lot of companies will say there product is < 60,0000 and not go into detail.

Is the GM spec NEW? I though that a few years ago the ASTM test was revised and the max 30,000 was doubled to 60,000 and the temprature which is tested at droped 5 deg.

Bruce

 

[shanneba]

The Castrol Syntec 5w-30 and10w-30 that meet the GM 6094M spec compared to CG 0w-30 From the current Castrol Spec sheet is:

...................................GC......10w-30
100C cst..........................12.1.......10.1
Low temp C Cranking [email protected]@-25
Low temp C Pumping [email protected]@-25

.................................5w-30
100C cst..........................9.7
Low temp C Cranking VIS......6600@-30
Low temp C Pumping VIS......40000@-35

 

[HALSTEADTW]

I wonder how it compares to a regular or synthetic (5w-30) around 0 degrees F? Anybody have any info on this?

 

[novadude]

I found the limits for the GM spec here:

http://www.imakenews.com/lng/e_article000098055.cfm

Why do Syntec 5W-30 and 10W-30 both meet the spec, but GC does not?

 

[lyle]

I'm running GC now, but its published cold weather specs scare me just a little, regardless of the 0W rating. When winter comes, I'm switching back to my old standard M1 0W-30, which I KNOW the Expy just loves when it's cold outside. I might even mix in 2 or 3 qts of 0W-20 just because I can.

 

[pscholte]

quote:

---

Originally posted by lyle:
I'm running GC now, but its published cold weather specs scare me just a little, regardless of the 0W rating. When winter comes, I'm switching back to my old standard M1 0W-30, which I KNOW the Expy just loves when it's cold outside. I might even mix in 2 or 3 qts of 0W-20 just because I can.

---

All I can tell you is that Castrol highlights winter conditions in describing the attributes/benefits of this oil. I used it during last winter in two vehicles, both of which sit out during the day while my wife and I are at work and had no problems.

 

[Blue99]

Here's the list of GM 6094M Approved Motor Oils .

Note that the M1 EP grades are missing from the list. The GF-4 rating is the key and the reason why GC 0W-30 is excluded, but the Castrol Syntec 5W-30 & 10W-30 grades are included.

 

[HALSTEADTW]

I understand that GC is good at -40 F but it never gets that cold here. Maybe around -10 F a few days a year. I'm really starting to wonder how good it will be compared to a regular sythetic around 0 F. Anybody have any hard numbers?

 

[bruce381]

quote:

---

Originally posted by lyle:
I'm running GC now, but its published cold weather specs scare me just a little, regardless of the 0W rating. When winter comes, I'm switching back to my old standard M1 0W-30, which I KNOW the Expy just loves when it's cold outside. I might even mix in 2 or 3 qts of 0W-20 just because I can.

---

0w is 0w no matter if comparing 2 oils there maybe a slight dif in cp at the test low temp
but if it meets 0w its 0w there is to betweens.
bruce

 

[21Rouge]

quote:

---

Originally posted by lyle:
When winter comes, I'm switching back to my old standard M1 0W-30, which I KNOW the Expy just loves when it's cold outside.

---

I apologize in advance as I bet there are threads talking about M1 0W-30. But do so many of you prefer GC over M1 0W-30 because of the superior UOAs? At first glance M1 0W-30 looks appealing because....

it is part of the M1 fine family of synthetics

it is a 0W

AND last but not least it is energy conserving (unlike GC)

(and related to this last point is that it is more than likely warranty approved for most cars...again unlike GC.)

Arent these good enough reasons to use it?

 

[vad]

Is that a rhetorical question?

 

[lyle]

quote:

---

0w is 0w

---

Correct, but as GC is a "thick" 30 compared to M1's "thin" 30 at the high side of the temp spectrum, I believe M1's 0W is "thinner" than GC's 0W at the low end of the temp spectrum.

 

[bruce381]

Correct there is a range both hot and cold
but he was asking about cold end no?
bruce

 

[Paranoil]

The pour point of Castrol SLX Longtec 0W-30 is -54C

For Mobil 1 0W-30 it's -45C

 

[21Rouge]

quote:

---

Originally posted by Paranoil:
The pour point of Castrol SLX Longtec 0W-30 is -54C

For Mobil 1 0W-30 it's -45C

---

But isnt it 'pumpability' that is the key stat for cold weather performance?

 

[vad]

IMO the key stat would be the CSS values (Cold Crank Simulator).
Castrol provides some data in that respect for its SLX Longtec.
Castrol's CSS is 5800 at -35C which is pretty low=good for the extreme cold start-ups.

Mobil doesn't provide any info.
Wonder why.