It's not cold for you but it's called for the oil.
Here, right now is back to 20°F with 16 miles wind. Bring that SAE40 to show us who's the man!
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HPL SAE 40 PCMO
- Thread starter Hohn
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Here, right now is back to 20°F with 16 miles wind. Bring that SAE40 to show us who's the man!
And no one would ever consider a straight SAE 40 in that weather. Not even close. He is not recommending it for that temp range either. No one is arguing against you. Sometimes I wish you could require a reading comprehension test you had to pass before you could comment in the thread.
I think it would start just fine. Wind doesn't make a difference in this situation either.
I'll let him clarify, but I want to say that he's thinking 15F is the bottom end of where he would use this oil.
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I'm not arguing with anyone,just making an observation about the cold weather
I passed English and German classes also.
The wind doesn't make difference about the ambient temperature but it makes different about convection. Which means your engine needs longer time to get up to operating temperature when is below 32°F and there is wind.
I think Hohn said that 15°F is the bottom line for 15W-40 (on paper is -4°F). I don't think is healthier to try also SAE40 at that temp.
Dash display said 29F. It was blowing snow but not sticking to the ground. I didn't leave for lunch so it was a true cold soak from 7AM to 4:30PM.
This morning it was 18F but the car was garaged, so that doesn't count.
The complete absence of mechanical noise is messing with me a bit. You can hear the exhaust but almost nothing else. At idle, I can now here the subtle whine of the turbo.
EDIT whoops, I missed the other posts.
I grew up in ND. I know what cold is. I had my eyes frozen open from tear-sicles in the lashes at -37F ambient (wind chill -50s). I looked it up, it was Jan 10, 1990. I remember that after we'd all made it to school (eventually) they dismissed us before lunch when it was clear the main doors were freezing shut and the custodial staff couldn't keep them accessible. (heat from the building was escaping and melting driven snow, which would re-freeze instantly, causing a layer of ice build up on the door cracks and that was felt likely to make us captive inside the building).
This is a cold start for SAE 40. And it's a useful data point in the context of rebutting those who were clutching pearls when I recommended SAE 40 for someone in Southern California.
The only time I have ever recommended SAE 40 was when I was quite obvious that cold starts below freezing were not a part of the duty cycle. As I've said before, my Dad in Bismarck is running 0w-40 Mobil 1 at my suggestion.
The bigger picture is this: far too many people are looking only at the oil's viscosity based on a couple points on the curve without considering the entire curve.
The entire CCS and MRV construct evolved because of the way oils transition to non-Newtonian behavior when cold and the waxes in conventional oil start to precipitate out. That's why MRV has the slow-cool provision in the test.
But what if you have an oil with little to no wax? GTL has only trace amounts and PAO has none. Suddenly the whole transition-to-non-Newtonian isn't even a thing anymore because it's newtonian all the way down.
This is why you have the phenomenon of HPL oils in "w" grades that are far, far below the MRV viscosity limit. IT's an artifact of J300's assumed waxing.
HPL formulation in cold weather are always CCS limited. And the CCS limits are VERY conservative. Very, very few cars cannot crank a 6500cP oil because their starters and batteries are incapable. But that's the thing: the starters and batteries are the limit, not the oil per se. If you can get the engine to fire, the oil will flow and flow freely.
I'm garaged. This afternoon returning from work will be about the same temp, but no need to replicate the prior validation that it cranks at temps just below freezing.
This entire proposition (SAE 40) stands mostly on my experience with the 15w-40. But I have no idea just how disparate they are in real world cold cranking. Such is the nature of a monograde. I was legitimately concerned about the unexpected cold snap causing a difficult crank. But with each successful colder start on this oil, I'm getting less concerned.
It's hard to describe how this oil "feels" so much smoother than the 15w-40 in terms of the subjective perceptions. Your ears can absolutely perceive something significant and it seems more than what a few points of KV40 could explain.
With the cold weather and crazy high winds, the MPG is not demonstrative yet, but it is anecdotally down by 1-1.5mpg. We'll know more after the first 1000 miles or so as the first 100 miles aren't representative in the way the prior 4400+ mile datasets on mpg are.
Some of the mpg disparity would be explained by my new habit of using Sport mode on a cold engine to keep RPM up and try to get the circulating more when cold. The higher shear per mile helps warm the oil faster but it also burns more fuel. No surprise that it costs fuel to get more heat into the oil.
Dude always arguing tbh
Different application, but it was mentioned here previously. A vintage bike mechanic who was a career Honda technician, among other places, Mike Nixon had a small work diary from a year or two ago on experimenting with different oils in his CB500/4 including SAE50. The biggest take away for that (which is an air cooled engine) was that it drove up the warm up time significantly. Something worth considering depending on the engine and how short your trips are: https://www.motorcycleproject.com/cb500/cb500_winter_2024.html
Not an issue for my car. It started fine with full cranking rpm at 28F on my return commute this afternoon and the heat started blowing 2 blocks later. The car sat 9 hours in the cold while I worked.
Minor update: 100 miles into the SAE40 and mpg has gotten within 1mpg of my long term average of 29mpg.
This, despite a very cold snap and some brutal headwinds on my drive.
I’m confident that the economy in better weather will largely close the gap and get back the high 28.x range.
This, despite a very cold snap and some brutal headwinds on my drive.
I’m confident that the economy in better weather will largely close the gap and get back the high 28.x range.
The pumpability temperature in the SAE J300 W rating is the minimum use temperature shown in the 2nd chart for the multi-grade oils. 20W would be -20C (-4F) and 25W would be -15C (5F). Straight SAE 30 is shown down to -4C (25F) and straight SAE 40 is shown down to 10C (50F). Typically, owner's manuals will be a bit more conservative than the 2nd chart ... I know it is for my Yamaha XSR900 motorcycle for instance when comparing the 2nd graph to the Yamaha owner's manual temperature vs oil grade chart.
Didn't read the whole thread, so did HPL ever give any equivalent "W" rating for their straight grade 40? That's the only real way to know what the viscosity is down in the W region of SAE J300.
Didn't read the whole thread, so did HPL ever give any equivalent "W" rating for their straight grade 40? That's the only real way to know what the viscosity is down in the W region of SAE J300.
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If anyone wants to read a good paper (SAE 922287) on oil performance at low temperatures, the PDF can be downloaded - link below.
https://www.savantgroup.com/media/SBT-SAE-922287.pdf
https://www.savantgroup.com/media/SBT-SAE-922287.pdf
It's a 40 grade, so when at 100C and 150C the kinematic viscosity and HTHS viscosity are thicker than any viscosity less than a 40 grade. Don't know what you mean in the bold part in your post.
Why not just use the HPL no-VII multi-grade? Then you know the W rating of the oil.
Only way to really know is if HPL ran that oil through their CCS and MRV test machines to determine where it falls in the W grade section of SAE J300.
In the paper linked in post 254, they talk about how newer engines with fuel injection start much easier in cold weather. Re: part in bold ... the limit of the oil is the pumpability viscosity in SAE J300. If an engine happens to start when the pumpability viscosity is beyond the W rating, then engine damage could occur. If the engine starts, the oil better be pumpable, otherwise oil starvation will happen. The SAE paper in post 254 talks about that.
Thanks for the info and the charts!
However, it looks like on the 2nd chart the W temps of the multigrade oils are 5 degrees lower than those I've seen on various oils PDS.
0WXX oils should be -35*C (not -40*C)
5WXX oils should be -30*C
and etc. for the rest.
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What spec are they showing on the PDS? I don't think a PDS shows the pumpability temperature, but the cold cranking temperature. SAE J300 lists both, and the pumpability spec is 5 deg C lower than the cold cranking spec ... I mentioned in the post that the 2nd chart shows the W grade pumpability temps.
Like I mentioned earlier, the pumpability spec is 5 deg C lower because they want to be sure that if an engine starts the oil will pump, so it's a more stringent hurdle for a W grade rating.
