Engine wear at warmup has little to do with oil flow and is mostly due to excessive fuel spray, moisture, and part clearances being way out of whack.
Obsolete grade/type: 5W-20 synthetic?
- Thread starter The Critic
- Start date
I'm still confused as to how a grade becomes obsolete, it may fall into disuse but it's not obsolete in the sense as no longer useful. The 900 MHz car phone in my old BMW became obsolete when there was no longer a cellular network to support its use. Analog television became obsolete when those signal transmissions were discontinued.
As far as I know many 10W-30 grades are API SP, so it's not as if they are API SG which is an obsolete API license. Most 5W-20 oils have most if not all the required licenses or specifications any modern vehicle might list in the owner's manual.
As far as I know many 10W-30 grades are API SP, so it's not as if they are API SG which is an obsolete API license. Most 5W-20 oils have most if not all the required licenses or specifications any modern vehicle might list in the owner's manual.
by warm-up I meant cold starts and the subsequent "warm-up".
The sooner oil gets to the moving parts the better. No?
As long as it is pumpable it gets where it needs to be. The winter rating is what demonstrates pumpability.
Yes, However, I am proceeding with caution.
For some reason I fell better if not in the borderline territory when it comes to the W. I like to have about 10-20F degree of margin. For example if 10W just barely meets my winter rating, then I move down to 5W.
If a 5W or 0W barely meet my winter rating, then block heater. lol
I may even use block heater if I was at the limits of 10W but I'm far from it.
10W will meet any winter requirement I've ever seen in Western Washington. I think your record all time low i Bremerton is 7.0°F.Yes, However, I am proceeding with caution.
For some reason I fell better if not in the borderline territory when it comes to the W. I like to have about 10-20F degree of margin. For example if 10W just barely meets my winter rating, then I move down to 5W.
If a 5W or 0W barely meet my winter rating, then block heater. lol
I may even use block heater if I was at the limits of 10W but I'm far from it.
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And also down to the fact that the main antiwear additive in oil (ZDDP) doesn't really 'wake up' until it's warm, so you are relying on only hydrodynamic protection.
Oil pumps are positive displacement, so assuming an oil can pump then the amount that gets pumped will be largely unconnected to the viscosity. What does change is how much energy is required by the pump to move the oil, which will come out of the engine's available power - a thicker oil will put more drag on the engine and hence cause it to use more fuel to maintain a given speed.
The reason MRV was introduced is that it not only measures an oil's resistance to pumping, but it also, critically, measures an oil's tendency to form a gel-like structure when it has been cooled slowly. Oil with this structure will still pump but it can be enough to prevent the oil from flowing under its own weight, meaning that the oil pickup can suck oil from the sump and eventually create a crater in the surface which doesn't backfill itself, leading to oil starvation. This is what happened during some cold winters decades ago, so the MRV test was introduced which includes a detection for yield stress - if any yield stress is detected the result is a fail, regardless of the apparent viscosity.
@weasley
I think my problem is watching one video. These days i don't pay much attention to pour point when I buy oil. On top of that, we have mild winter temperatures and I am using mostly 10W.
Regarding the video:
I don't remember what engine it was but oil was pumped to upper parts of the engine and was dripping down through some tiny holes under I assume no pressure.
so I was thinking if oil A and B (with the same W rating) can be "pumped" but B flows slower than A and takes longer to get to where it is supposed to go ... which one would I prefer?
I am also assuming oil A has a significantly lower pour point temperature. Let's say dino vs. syn with the same W.
Maybe it's all insignificant but it makes me wonder.
I think my problem is watching one video. These days i don't pay much attention to pour point when I buy oil. On top of that, we have mild winter temperatures and I am using mostly 10W.
Regarding the video:
I don't remember what engine it was but oil was pumped to upper parts of the engine and was dripping down through some tiny holes under I assume no pressure.
so I was thinking if oil A and B (with the same W rating) can be "pumped" but B flows slower than A and takes longer to get to where it is supposed to go ... which one would I prefer?
I am also assuming oil A has a significantly lower pour point temperature. Let's say dino vs. syn with the same W.
Maybe it's all insignificant but it makes me wonder.
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If you use the same type of base with lower viscosity in the 0W-20 that's true but often the 0W-20 has a higher VI base stock and in that case may have less VII. I've often thought the issue might be a concern about the VII in the few 0W-20 Blends available.
I personally would not be afraid to run 0W-20 (5W-20 spec vehicle) but would be selective about the ones I chose.
However, expecting the average consumer to deviate from whatever is on the oil cap is not something I see happening in any great numbers so I don't see it becoming obsolete anytime soon. 10W-40 isn't yet obsolete and it's been a while since new cars have specified it as the primary grade.
Yeah I was too lazy to add that part.
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