Thick vs. Thin

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Drew7a

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I guess it all comes down to the following:

We all can agree, thin pumps better when cold and thick generally has better HTHS#s which can be construed to mean better protection.
Therefore thick and thin both protect.

I guess I did not realize that this is such a contentious topic.

Pick what is important you, there is no one size fits all.

To me personally 0w-30 would the sweet spot for majority of things I maintain and climate where I live. Since I like oil sales and 0w-30 is hard to find on sale or almost free, my oil Stash is 85% 0w-20, 5w-30 for gas applications and change the grade based on the seasons and blend as well depending what partials I have left.

Been in the low single digits for a high all last week. and even the diesel tractor with T-6 5w-40 starts right up without a heated block in an unheated shed.
 
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Does anyone know if the auto makers are legally required to recommend only the oil which was used during certification?
Yes, they have to recommend the oil viscosity they used to meet the fuel economy rating.

Hyundai/Kia has somehow skirted around this in their owners manuals and have yet to get in legal trouble.

Hyundai OM’s basically say this, “5w-20 is recommended for max fuel economy, but we want you to use 5w-30or 10w-30”.
 
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Good morning Vietnam! Correct, you'd need to register with an e-mail address, I shall try tro show you later behind the curtain, don't want to really plaster with more pics, the scans are what the login would get you...

Listen, the relief ain't important when we're not after judging PDP magic – which we aren't. The engine is what it is and between oils it got flushed, motored, then cooled. Why would they try to motor the thing around after blowing the dendritics dry between measurements? For special repeatability?
For your inspired peer review log in or don't but don't expect me to chase ideas of emergency exits for you.

Tell me instead: For the 5W-40 in -15°C you'd make its MRV of 13000 cP how much lower?
Will this fiction help us to explain the still sixfold delay for the rocker shaft between 34 s and 5.5s (main gallery)? Similar with the 10W-30 (8x).?
Or is your explanation getting lost somewhere between these six oils?
(In the Cummins that might not even send through hollow pushrods – okay, that I should look up for you.)

Yes, many factors all the time, things get stacked, even times along galleries and pushrods get stacked. Ramifications for molecules are mere offers: A main bearing entrainment or blob somewhere now or a rocker arm in 48 seconds to five or six minutes if need be. Many will just choose the main bearing entrainment where it's already getting warmer instead of lining up for the cold rest of the vulcano.
Get over it. PD shoving is looking backwards at the pump characteristics but never looking forward at the lubrication. One for all via one common flange means an input only to the total while no control whatsoever is possible over the balance, the ratios, the bias, the mobilé, the differentiation... The fundamental principle is shown.
A multiple elements pump, a dedicated oil metering pump that had six plungers like mine in the rotary, could serve your ideas for six main branches in subtotals or individual points of lubrication but PD as such is usually irrelevant for answers on BITOG. Balances are free, ratios change.

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Alright blingo ... good info. I figured the engine was ran and galleries were "full" before cooling for a cold start-up, but had to be sure.

And it doesn't specifically say, but I'd bet they didn't do anything to change the operation of the PD pump pressure relief operation ... so that is going to be a large factor on how the pump operates in these super cold oil pumpability tests. The PD pump is no doubt going to be in pressure relief upon initial start-up in these conditions, and therefore oil volume going into the oiling system will be cut back ... and flow volume could be cut back quite a bit.

These tests are testing start-up operation in extremely cold conditions (very near or at the pumpability limit), with various oils to find the limit of some kind of defined adequate start-up lubrication ... so the pump pressure relief is obviously a big factor here since it's part of the engine design. In a super extreme case, the oil could be so un-pumpable that virtually no oil leaves the pump and the engine will destroys itself.

Just want to clarify that I'm not claiming that as the oil gets closer and closer to not being pumpable that the PD is going to still operate 100% effectively. I've said in many post in this thread that near the ragged edge of the oil pumpability all kinds of things are going on with the oil getting pumped - and there are many factors going on from the specific oil formulation to the specific design of the PD pump, the pump inlet feed tube and the whole engine oiling system.

But when the oil viscosity is well above the pumpability limit, then a PD pump is going to operate 100% how it's intended to operate, as discussed in the other thread about the piston cooling jets "not operating correctly" (as 'MC Professor' claimed in the video) if the viscosity isn't what's called out by the automaker. Fact is, PD pumps and oiling systems are not that sensitive when the oil is at operating temperature or well above the oil pumpability limits. But when oil as at or near being un-pumpable, then yes they are sensitive as these oil pumpability studies show.

The fact is, even though in some cases the oil takes longer to flow into the pump, get pumped into the oiling system and build pressure in these super cold start-up conditions, it's still considered adequate lubrication for the conditions at hand if lubrication happens within some kind of defined limits (see graph below from a link I'll give also). And only a PD pump is able to achieve this kind of operation in cold climates ... a centrifugal pump or similar wouldn't province any lubrication under these conditions (see post #72). Bottom line is that there certainly is an oil viscosity limit where pumpability even with a PD pump quickly degrades ... that's the focus of these studies. How a PD pump and oiling system works with 100% pumpable oil is pretty much the norm for engines unless you live in a super cold location and use an oil too thick for the conditions ... then you see what these studies show.

If I lived in a super cold part of the country I'd probably be using a 0W-20 or 0W-30 to ensure the best cold pumpability as possible.

Here's a link to a similar study conducted by the SWRI in 1987 for the US Army ... interesting and similar findings when trying to pump oil on the ragged edge of pumpability. Study summary Figure 19 on page 39 carefully, and you can see just how much a specific engine system/design can be effected by the oil's pumpability.

1987 SWRI study for the US Army:
Typical Oil Traces Graph.JPG
 
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With this I'll just leave you to your ping pong. Still no sense in anything here, so I've got better things to spend my unintelligibility on than that where people never want to know. Baba
... "still no sense in anything here" ... huh? Guess you really don't get that people here are pretty much agreeing that when trying to pump super thick oil near the oil's pumpability limits, that oil pumps and oiling systems are certainly effected in that operational realm. But people also need to understand that when not in these difficult pumpability scenarios that the PD pump and oiling system operates in a very different way ... like it's meant and expected to operate. And that means 'Mr MC Professor' is blowing smoke in the other thread about his comment on piston cooling jet operation ... these are different scenarios that can't be equally compared.
 
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If you ask me: Your only chance would be to go back and start all over. Read both threads from the beginning of the first one – just for fun decidedly ignoring each and every one of your own entries. A small chance that would be.

But you're fine, ZeeO! Really. You're not the problem, neither you nor others of your kind. The rest of the forum is. The rest and me. Me, who throws good unintelligibility after bad to – from the third or fourth entry in such a thread – only prove that I'm not the brightest...

Again, ZeeO: You're fine. In these new short sentences of mine. You're just killing yourself the way you're thinking. Thinking you'd be breaking up others entries and be answering them or whatever. That's why your only chance would be to...
 
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If you ask me: Your only chance would be to go back and start all over. Read both threads from the beginning of the first one – just for fun decidedly ignoring each and every one of your own entries. A small chance that would be.

But you're fine, ZeeO! Really. You're not the problem, neither you nor others of your kind. The rest of the forum is. The rest and me. Me, who throws good unintelligibility after bad to – from the third or fourth entry in such a thread – only prove that I'm not the brightest...

Again, ZeeO: You're fine. In these new short sentences of mine. You're just killing yourself the way you're thinking. Thinking you'd be breaking up others entries and be answering them or whatever. That's why your only chance would be to...
I don't know man ... I know it's kind of complicated, but these conversations have to really be kept in context to the operational scenarios at hand.

Those piston cooling jets are going to operate just fine (as well as the whole lubrication system) in any engine (because of the PD pump) with any half way warm oil (far from the extreme lose of pumpability) regardless if it's 0W-8 all the way up to 20W-50. But take all those oils and start trying to fire up a stone cold engine at -20F and the way the oiling system behaves is going to be all over the place, and it will be different for every engine oil and engine combination. Trying to compare two extreme operational cases really needs to be kept in context, and can't be "cross compared" very much at all.

It's all good debate subject matter IMO, and thanks for the exchange.
 
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Paint me a volcano.

Brillant idea! Prime example why every second expression of mine should be googled. I'm mostly relying on people to do more or less exactly that, in case they wanted to follow. In this case not even I had an idea this would potentially work out so great. I merely thought spontaneously I'd encourage: Paint me a volcano! Maybe in oil. Only then by second thought: Wait, I need to double check via google, images.

Problem with debate was: Pages here and pages there, but no argumentation. So I discard the debate.

Maybe painting in oil would work.

Good night.
 
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Paint me a volcano.

Brillant idea! Prime example why every second expression of mine should be googled. I'm mostly relying on people to do more or less exactly that, in case they wanted to follow. In this case not even I had an idea this would potentially work out so great. I merely thought spontaneously I'd encourage: Paint me a volcano! Maybe in oil. Only then by second thought: Wait, I need to double check via google, images.

Problem with debate was: Pages here and pages there, but no argumentation. So I discard the debate.

Maybe painting in oil would work.

Good night.


Obvious trolling.
 
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Thank you, PimTac! Hadn't thought of the report-button. I shall immediately see what I can do for you by reporting me.
 
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My mom's car will soon see 400k on 5w20 GTX since she's owned it. 3-5k mile oil changes(usually 3k) and mainly Wix and Baldwin filters with some Fram orange can in the beginning and some other odd ones here and there. Oil analysis is still good.
 
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My mom's car will soon see 400k on 5w20 GTX since she's owned it. 3-5k mile oil changes(usually 3k) and mainly Wix and Baldwin filters with some Fram orange can in the beginning and some other odd ones here and there. Oil analysis is still good.
To a great degree, the act of consistent, reasonable OCI's and other general maintenance will take most vehicles into the 200,000+ miles arena. It has for me.
 
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To a great degree, the act of consistent, reasonable OCI's and other general maintenance will take most vehicles into the 200,000+ miles arena. It has for me.
We have always run vehicles to the 200,000 area. So much so that I would even buy a high mileage vehicle without worry. I learned in the OTR truck world that sometimes mileage is not a true representation of something. A million mile plus tractor wouldn’t scare me a bit either if everything else checks out.
 
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I am in the mindset that there’s a middle ground that your thick and thin combination is almost perfect. In diesel tech school they taught us that the majority of engine wear occurs on startup (I can’t remember the % they said) therefore it is incredibly important to get oil flowing as soon as possible. This is where the lighter grade is important. Once warmed up though you want a HTHS that is better in a 30 than say a 20. I am a fan of 5w40 in my diesels for exactly this reason.
 
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