CCS Changes with Use?

[Blake1107]

Apologies if this is covered somewhere multiple times. I've tried phrasing my question basically and with terminology that may be used here on BITOG in the Search function, and I have failed terribly.

What I am wondering is, with the use of oil, how much does the ability to flow from cold start change? Is there an equation or algorithm for so many miles of use = so much change in CCS?

I am using 10W30 right now. Chose it because the NOACK nearly cut in half from 5W30, the HTHS is a little better, and the CCS change was from -22°F to -13°F. Southeast MO temps RARELY go negative, unless you factor in windchill and then the "feels like" can go sub-zero. This past week is a good example as we have seen temps get to 0°F briefly overnight and "feels like" temps have been as low as -16°F. My last two morning cold starts have been at ambient temps of 6° and 9° ("feels like" for both were sub-zero). The truck was a touch slow to fire-up and accompanied by higher-than-normal RPM's. The oil is 5 months old and has about 3.5K miles of use (a lot of it being trips ~25 miles of less). Truck is always parked outside, too.

I am assuming (from a few of the discussions that came up with some info) that with use, the specs of my oil have changed/degraded, but I couldn't really figure out if there was a way to determine or estimate by how much. With the stats I gave for my current OCI, could the CCS have been impacted enough to move from -13°F to 0°F or higher? Also, is CCS ambient temp or should I use the "feels like" temp as the standard? Lastly, is there a chance those two cold starts could have been dry or the filter in bypass for an extended period and caused damage to anything?
Wasn't really expecting a cold like this in SeMO this winter, but I think from now on I'll be using 5W30 or 0W30 for the winter months to avoid this being a concern again.

Thanks in advance for sharing your knowledge!

 

[Rand]

"Feels like" is wind chill it does not apply to machinery.

I'd be more interested in the MRV number which is considerably more important that CCS or Pour point.

 

[Blake1107]

"Feels like" is wind chill it does not apply to machinery.

I'd be more interested in the MRV number which is considerably more important that CCS or Pour point.

What is MRV and is that a normally listed spec?
I have checked some Amsoil, Mobil 1, and Valvoline PI sheets I have saved and none list "MRV".

 

[racer12306]

"Feels like" is wind chill it does not apply to machinery.

Agreed

The only factor windchill would have is how quickly it will cool down when shut off.

 

[Rand]

What is MRV and is that a normally listed spec?
I have checked some Amsoil, Mobil 1, and Valvoline PI sheets I have saved and none list "MRV".

here is an old bitog post about it
it was from old forum software so some of the "quotations" are missing try not to get confused seeing text from previous posts without quotes from the previous poster.

Thread 'CCV and MRV significance'

Feb 3, 2015

Straight from the ASTM website:
Quote:
CCS apparent viscosity is not suitable for predicting low temperature flow to the engine oil pump and oil distribution system.

Quote:
A correlation was established in a low temperature engine performance study between light duty engine startability and CCS measured apparent viscosity. This study used ten 1990s engines at temperatures ranging from –5 °C down to –40 °C with six commercial engine oils (SAE 0W, 5W, 10W, 15W, 20W, and 25W).8


It is a rough estimation for the cold engine startability. CCV should by no means be used as the basis for cold...

• KrisZ
• Replies: 19
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

 

[Blake1107]

I came across this post as well.
Tom NJ has a very easy to understand explanation of what each test is measuring. (Edit: seems it is in your shared post as well).

If MRV is not a stated spec, is there a way to find that? Is that something tested for in a VOA?

Thread 'ASTM D5293 (CCS) vs. ASTM D4684 (MRV)'

Jan 9, 2022

As I do lack deeper understanding of both ASTM D5293 and ASTM D4684 I'd highly appreciate
some help.
Apparently ASTM D5293 is for CCS viscosity while ASTM D4684 is for MRV/low temp. pumping
viscosity. I came across a seemingly odd observation while comparing the datasheets of both
Ravenol REP 5W-30 and VMP 5W-30. To me they don't correlate the way I had expected. When
both are similar base oil composition (which is just an assumption), similar kinetic viscosity and
exact same pourpoint, shouldn't the oil with the lower CSS also exhibit the lower MRV? If it isn't
the case, should I...

• 930.engineering
• Replies: 17
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

 

[twX]

CCS and MRV are both allowed to thicken by around one grade after an aging test. The aging process used is a lot more severe than what an oil would experience over an appropriate OCI. It's not something to be concerned about if your OCIs are reasonable.

MRV relates to how well the oil in the sump will flow down to the oil pump pickup. If it's too high, the oil pump may start sucking in some air. MRV will only ever matter when the temperature is getting close to the MRV test temperature (-30°C for a 10W). In less extreme cold like in your climate, it should be completely irrelevant.

CCS is still relevant at less extreme temperatures. It will affect engine friction while the engine is cranking or running. It will also determine how quickly oil gets to the bearings after a cold start, and it should also affect the likelihood of oil filter bypassing. Thicker oil also means higher engine load, and therefore more load on the bearings while lubrication conditions are marginal in the first seconds after a cold start.

I'd use a 5W in that weather, even though a 10W is technically rated down to -25°C. I wouldn't worry about having done any damage to the engine.

 

[Blake1107]

Thank you for that, @twX !

 

[Alien]

Post in thread 'Mobil 1 Classic 0W30: best cold weather oil?'

Feb 14, 2024

I came across this 2018 paper “Cold cranking viscosity of used synthetic oils originating from vehicles operated under similar driving conditions” that measured how much CCS @ -31C increased for various 5w30 oils over a 1 year period with accumulated mileages up to 15,551 km. The oils used were not identified but grouped according to their certifications. Their conclusion (edited by me to more clearly identify and distinguish the oil groups):

“All analysed oil groups showed an upward trend in the dynamic viscosity at −30°C compared with the baseline value, and the sharpest increases...

• Alien

• 

 

[Blake1107]

@Alien , from what I read there, would this be correct?
It could be safe to assume my oil was still working appropriately since it is less than a year old, only 3.5K miles on it, and no extended exposure (or any exposure at all) to the -25°C used for testing.
But the oil is approaching a state of needing replaced if weather like we just experienced was to happen again.

 

[Alien]

@Alien , from what I read there, would this be correct?
It could be safe to assume my oil was still working appropriately since it is less than a year old, only 3.5K miles on it, and no extended exposure (or any exposure at all) to the -25°C used for testing.
But the oil is approaching a state of needing replaced if weather like we just experienced was to happen again.

I haven't carefully studied this analysis since I posted it last year, but my recollection is that they did not differentiate between milage and exposure to cold temperatures. I don't think exposure alone would modify the oil, but the combination of milage and exposure might. But I am by no means an expert on this.

 

[FZ1]

Apologies if this is covered somewhere multiple times. I've tried phrasing my question basically and with terminology that may be used here on BITOG in the Search function, and I have failed terribly.

What I am wondering is, with the use of oil, how much does the ability to flow from cold start change? Is there an equation or algorithm for so many miles of use = so much change in CCS?

I am using 10W30 right now. Chose it because the NOACK nearly cut in half from 5W30, the HTHS is a little better, and the CCS change was from -22°F to -13°F. Southeast MO temps RARELY go negative, unless you factor in windchill and then the "feels like" can go sub-zero. This past week is a good example as we have seen temps get to 0°F briefly overnight and "feels like" temps have been as low as -16°F. My last two morning cold starts have been at ambient temps of 6° and 9° ("feels like" for both were sub-zero). The truck was a touch slow to fire-up and accompanied by higher-than-normal RPM's. The oil is 5 months old and has about 3.5K miles of use (a lot of it being trips ~25 miles of less). Truck is always parked outside, too.

I am assuming (from a few of the discussions that came up with some info) that with use, the specs of my oil have changed/degraded, but I couldn't really figure out if there was a way to determine or estimate by how much. With the stats I gave for my current OCI, could the CCS have been impacted enough to move from -13°F to 0°F or higher? Also, is CCS ambient temp or should I use the "feels like" temp as the standard? Lastly, is there a chance those two cold starts could have been dry or the filter in bypass for an extended period and caused damage to anything?
Wasn't really expecting a cold like this in SeMO this winter, but I think from now on I'll be using 5W30 or 0W30 for the winter months to avoid this being a concern again.

Thanks in advance for sharing your knowledge!

Big picture. If the cold weather start is noticeably more difficult, then consider a lower grade for winter starts.

 

[Patman]

This is why it’s always a good idea to have a fresh batch of a 0w oil in there if you are in an area where the temperature can get really cold in the winter. A 5w oil is good enough to some pretty cold temperatures when new but keep in mind that depending on how many miles you put on, it might slip to a 10w part way through the winter. So for better starting performance you can either start out with a 0w oil or do a mid winter change to some fresh 5w so that you aren’t faced with having to start on a -40 day with a 10w oil.