How oil characteristics change throughout an OCI

[mbacfp]

Are the cold properties of an oil reduced throughout an OCI? For example, 0w-20, if one is at 80% through an OCI does the 0w part degrade or become less effective in cold situations? Or is it's cold properties primarily due to base oil quality?

 

[Bryanccfshr]

As the oil ages it can begin to oxidize. Thickening the oil over time. I dont see why pour point depressants would not degrade and suffer oxidation degradation as well.

But then again the vast majority have oil that will never thicker enough not to pump in the weather we encounter.
I noticed you are in California and I am in Texas for example. We are not at risk of our oil not pumping due to cold weather. And I mean it got down to the 20's the other night where I am working..and I am not worried about the used oil in my sump. The truck started and ran. After sitting outside in the 20's!

 

[Danno]

Originally Posted by Bryanccfshr
As the oil ages it can begin to oxidize. Thickening the oil over time. I dont see why pour point depressants would not degrade and suffer oxidation degradation as well.

But then again the vast majority have oil that will never thicker enough not to pump in the weather we encounter.
I noticed you are in California and I am in Texas for example. We are not at risk of our oil not pumping due to cold weather. And I mean it got down to the 20's the other night where I am working..and I am not worried about the used oil in my sump. The truck started and ran. After sitting outside in the 20's!

I have started a Ford 460 cu in, not plugged in, questionable OCIs, at -45F.
At the time, 10W-30 was commonly used for oil changes.
It was in Timmins, Ontario, near the cold weather testing location for GM in Kapuskasing, Ontario.

 

[Bryanccfshr]

Originally Posted by Danno
Originally Posted by Bryanccfshr
As the oil ages it can begin to oxidize. Thickening the oil over time. I dont see why pour point depressants would not degrade and suffer oxidation degradation as well.

But then again the vast majority have oil that will never thicker enough not to pump in the weather we encounter.
I noticed you are in California and I am in Texas for example. We are not at risk of our oil not pumping due to cold weather. And I mean it got down to the 20's the other night where I am working..and I am not worried about the used oil in my sump. The truck started and ran. After sitting outside in the 20's!

I have started a Ford 460 cu in, not plugged in, questionable OCIs, at -45F.


I have worked in the Arctic And know what it sounds like when the oil is not pumping after startup. Sometimes they just couldn't turn over and we would have to tow the trucks to shops and heat the pans for a few hours. As a practice we usually didn't turn them off and ran them 24 hours a day once temperatures were 20 below or cooler. The diesels seemed to degrade cold rated 0w30 diesel oil faster than the gasoline vehicles . Soot most likely made it more solid in cold.

 

[Triple_Se7en]

I had no idea Northern Ontario gets that cold.
I won't go outside in -45.
Heck, I try to stay indoors at -10

 

[JC1]

Originally Posted by Triple_Se7en
I had no idea Northern Ontario gets that cold.
I won't go outside in -45.
Heck, I try to stay indoors at -10


Even in the Toronto area it can get down to -20c for a week or two during January or February. You can't stay inside forever.

Thank goodness my caravan has a block heater. They civic is in the garage so cold starts aren't that hard on it. Synthetic oil makes it start much easier as well.

 

[Snagglefoot]

Originally Posted by mbacfp
Are the cold properties of an oil reduced throughout an OCI? For example, 0w-20, if one is at 80% through an OCI does the 0w part degrade or become less effective in cold situations? Or is it's cold properties primarily due to base oil quality?


Thanks for bringing that up and certainly you don't have to worry about it in California. However, why not save some used oil, put it in your freezer and do a pour test vs some fresh oil of the same grade. Now you experts out there, don't get too excited, it's just an empirical test. I'm betting you will see a small difference.

 

[OVERKILL]

Originally Posted by mbacfp
Are the cold properties of an oil reduced throughout an OCI? For example, 0w-20, if one is at 80% through an OCI does the 0w part degrade or become less effective in cold situations? Or is it's cold properties primarily due to base oil quality?


In service, oils are allowed to slip a W-rating. Shannow has covered this rather extensively in the past.

PPD's work by reducing the temperature at which wax crystals form in the base oil. This is a characteristic of Group III, II and I; any base oil that has wax in it. Low-viscosity FT GTL base oils are better in this regard, having lower pour points than other Group III base oils.

PAO has no wax in it, which is why PAO bases have insanely low pour points.

An oil with a wax-containing base will hit a wall: its crystallization point where the viscosity drops off a cliff as the wax crystals form. This is one of the reasons that Pour Point is no longer used to determine cold temperature performance, because it was found that certain cooling/warming cycles changed significantly the temperature at which this occurred. The resulting product would be unpumpable at a temperature it was classified to pump at.

This is however why oils with significant slugs of PAO have very low pour points. A PAO-based lubricant can still fail CCS and MRV (generally CCS) for a given W-rating while still pouring at a much lower temperature. This is because PAO's performance is quite linear at these low temperatures; it doesn't have the viscosity "cliff" characteristic of a waxy base oil.

As Bryanccfshr noted, base oils oxidize, which causes them to thicken. PPD's and VII's both degrade in service and as such, the W rating will be impacted. A 0w-xx is allowed to become a 5w-xx and a 5w-xx is allowed to become a 10w-xx...etc. Whether this will actually happen or not of course depends on the type of service and the base oil combination used. A lubricant that's heavily PAO based would be, IMHO, far less likely to slip a grade than one that's Group III. PAO is more resistive to oxidation and it isn't depending on those PPD's to keep it fluid at low temperatures.

 

[benjy]

from experience i can say the 20-50 amsoil in a motorcycle stored in a garage prolly 30's to 40 degrees, i think amsoil was already "cheating" with cheaper group III synthetics over 10 years ago!! the bike s-l-o-w-l-y cranked until its small but good battery died!!

 

[OilUzer]

I can't recall, is xx (upper end) allowed to skip a grade (down)? Doesn't KV100 decrease by age? What happens to kv40?

 

[OVERKILL]

Originally Posted by OilUzer
I can't recall, is xx (upper end) allowed to skip a grade (down) also? Doesn't KV100 decrease by age? What happens to kv40?


No, I don't believe the KV100 is allowed to slip a grade.

Regarding KV100, it will either increase (oxidation) or decrease (VII shearing, fuel dilution...etc) depending on the operating conditions. It may also do both (one, then the other). KV40 will in turn change depending on what's causing the change in KV100.

 

[burla]

Originally Posted by mbacfp
Are the cold properties of an oil reduced throughout an OCI? For example, 0w-20, if one is at 80% through an OCI does the 0w part degrade or become less effective in cold situations? Or is it's cold properties primarily due to base oil quality?


Ever hear of youtube

Search youtubes, they have a bunch. Short answer vii's shred yes winter rating increases grade decreases at first, most 0w40's become 5w30's within 2500 miles.

[video:youtube]https://youtu.be/MVn5OzuHtjg?t=108[/video]

[video:youtube]https://youtu.be/V5a4kP-5Jiw?t=24[/video]

[video:youtube]https://youtu.be/tYkg0oDUXs8?t=345[/video]

 

[burla]

watch the last video first, there ya go, visual proof.

 

[StevieC]

Originally Posted by benjy
from experience i can say the 20-50 amsoil in a motorcycle stored in a garage prolly 30's to 40 degrees, i think amsoil was already "cheating" with cheaper group III synthetics over 10 years ago!! the bike s-l-o-w-l-y cranked until its small but good battery died!!

Yeah looks like Group 3 to me... Further with this low of a pour point there is no way you had issues cranking at far warmer 30-40 degrees unless you had some other problem going on like a weak battery or starter.

 

[Linctex]

Originally Posted by burla
watch the last video first, there ya go, visual proof.


Pretty startling - the change that occurred - - , all things considered

 

[zeng]

Originally Posted by burla
[video:youtube]https://youtu.be/tYkg0oDUXs8?t=345[/video]

Testing cold flow of 15W40 at -35F, with intention to educate or ...????
What a disappointment with EE.

 

[Linctex]

Originally Posted by zeng
Originally Posted by burla
[video:youtube]https://youtu.be/tYkg0oDUXs8?t=345[/video]

Testing cold flow of 15W40 at -35F, with intention to educate or ...????
What a disappointment with EE.


I think he borrowed that video clip from someone else...... I'm sure it's older than 2016

 

[madeej11]

Originally Posted by benjy
from experience i can say the 20-50 amsoil in a motorcycle stored in a garage prolly 30's to 40 degrees, i think amsoil was already "cheating" with cheaper group III synthetics over 10 years ago!! the bike s-l-o-w-l-y cranked until its small but good battery died!!
benjy, there must be something seriously wrong with you. All you ever post are Amsoil rants. Maybe it's some sort of sick little love-hate relationship with you and that company's oil. Please give it a break, it's not normal behavior.* Oh yeah, SS has plenty of Pao in it, you're just about the only one that doesn't know it.

 

[burla]

They certainly aren't cheating, they don't claim to use group 4 or 5, so how could that be cheating? And clearly you can't blame a battery dying on oil.

 

[pitzel]

Volatility of the lubricant reduces over the interval as higher vapour pressure components of the lubricant hydrocarbon mixture are boiled off in the ordinary operation of the engine.
Its for such reason that it is believed that intake deposits due to recirculated crankcase vapours are reduced when longer drains are used on the DI engines. Or stated differently, increased when short drains are used.

BTW StevieC, some of those "20W50" oils suspiciously look like 5W-50's based on specs, but are not marketed as such. Probably catering to the sort of people who might want a 20W50 possessing an unfortunate lack of lubricant knowledge.