They do measure some additives, like moly, phosphorous, boron, etc. Those are additives the oil blender put into the base oil.
Why do some cars call for 5W20, not 0W20?
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Just took a peek at that thread. It is a very long one with over 10 page discussions. So my comment here could be well premature.
It is hard to draw conclusions from a single graph without having access to the full paper. If the test did not simulate a cold start but just a stable operation with constant oil supply, then it makes sense that thicker oil provides better protection because it is in the regime of boundary lubrication.
However, the results do not represent the whole engine very well, because in an engine wear comes from a combination of hydrodynamic (bearings), elastohydrodynamic (cams, gears), and boundary lubrication. Any one of these failures will determine an engine failure. More importantly, lubricant may not be on the cylinder walls/rings readily at each cold start.
I admit that my opinion may change if I read all the discussions in that thread, due to the possibility of more data and information. If you have finished reading that thread, do you care to share it so that I may be able to get a "short cut" and get to know the conclusions?
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Yes but I don’t think that was a part of his/her question.
Completely agree.
I am confused here...
He said: "On the other hand, some video on Youtube claims it will take tens of seconds for oil to reach to all the interfaces."
You said: "I seriously doubt it takes tens of seconds for oil to reach everywhere in a engine."
I said: "Depends on the temperature and the oil used. Been quite of few discussions here on BITOG showing studies with measured times for oil to get to various regions of engines. When the pumpability of the oil becomes degraded due to temperature, then the times can become pretty long."
So that's why I said what I did ... regardless if that was part of the original question, it came up. And what I said was accurate.
I didn’t watch the video but that statement has to include the temperature in order to be valid. Just coming out and saying that it takes tens of seconds ( poor choice of words) to get oil throughout the engine is just bull hockey.
@ZeeOSix , I’m not disagreeing with you. My contention is with the YT video
@ZeeOSix , I’m not disagreeing with you. My contention is with the YT video
With all due respect, it is maybe a good idea to watch the video before rejecting its statement. Or better yet, please share your data of pumping time vs. temperature. I am here to learn.
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Go read this thread (link below) from the post the link pops you into it (post #31). Lots of back and forth about cold weather starting and oil pumpability. Yes, as the oil gets closer and closer to losing full pumpability then it will take longer for the oil to get from the sump to the pump. Once it hits the pump, if the pump relief valve isn't opening then all the parts of the engine that are force fed oil supply by the PD will get oil close to in the same time. But if the oil pumpability is really degraded, then it will take longer even to the force fed areas of the engine. In some of the graphs in the link below, you can see once the pressure starts building (ie, the pump is fully pumping) then the time rise to achieve good/full pressure is about the same, but the time to start building pressure is lagging due to oil pumpability being degraded. IMO, most of that time lag is the oil having trouble getting from the sump to the PD pump, and maybe some pump pressure relief action is also happening causing slower pressure build-up.
Thick vs. Thin
Too thick and oil WILL cause issues, too thin an oil WILL cause issues. There is a middle ground. You can have an oil that will provide better fuel economy and better wear resistance upon cold start / short trips (thinner). You can also choose a thicker oil that will provide better wear...
bobistheoilguy.com
No they measure the atoms, not the compounds. Sure sometimes you can guess but it's not as if you really know "the additives".
Blenders don't put in elements they put in compounds.
Why do the VOAs show ppm? That's a concentration level of the substance. If an oil has xxx ppm of Moly in it, then it has moly in it as an "additive" to the base oil.
Jackson_Slugger
$50 Site Donor 2022
I do and I love it!
Jackson_Slugger
$50 Site Donor 2022
The Mexico thing has been looked into and it means nothing relative to weights used in the US without looking at the market conditions. Synthetics like a Mobil 1 or Pennzoil/Helix 0W-20 are very expensive and hard to comeby. Even the synblend 5W-20's were pricey relative to here last time checked in early summer somewhere in a thread here. A 5W-30 "conventional" was more abundant. And some of the labeled off-brands didn't exactly inspire confidence regardless of weight...
Jackson_Slugger
$50 Site Donor 2022
They do ( maybe did in some cases) as does Honda, but they seem to be hard to find with the exception of maybe the Castrol (for now)...
This is above my paygrade, however some experts don't like the higher spread either. iirc, SOJ recently had a post about it as well as other experts in the past. Basically try to avoid larger spread if possible and not required ...
on the other hand, you see a few 0W40 oils having many European approvals and certs. So evidently not all the oils are the same.
when it comes to 0W oils, my understanding is that due to the superior base oil quality, they have a higher natural VI and that will compensate somewhat. That's why when it comes to 0W20 vs. 5W20, the higher spread of 0W20 is not as much of a concern.
The advantage of blend over full syn is?
Educate me: which base stock group does 0W20 and 5W20 use, respectively?
Jackson_Slugger
$50 Site Donor 2022
It's cheaper to blend and they still charge a premium for it at dealerships?
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