30w vs. 15w50 @ 25F

[twigdog]

So, I was adding a quart of oil to my wife's truck last night when I decided to do a rudimentary experiment. I had a quart of 15w50 Mobil 1 and a quart of 30w Havoline sitting there. The temps here have been about as cold as they get in winter. It's been in the teens at night and hasn't risen above 32 during the day for the last 3 days. Well, it was 25 out when I did my pour test. The thing we do sometimes. Long story short, I shook the bottles and the 30w seemed a little more fluid so I took the empty quart bottle I just poured out, stuck a funnel in and pout the 15w50 first. Well it would take 10 seconds for the funnel to drain when filled to the top. Thick stuff, small funnel. Then on to the 30w. All things being equal here, it only took 8 seconds for it to drain the same funnel. Now this brings me to my question.
Are 30w oils, or any single weight oils, oils that just don't make the cold, i.e. 10w, pour points? Like say a 15w30 or a 20w30?
I plugged the numbers in the chart that has been floating around here that uses the 40c and 100c temps and it showed the 30w doing way better than even 10w40. I don't know. Maybe just too bored in the cold. Still surprised that a 30w dino would outflow a 15w50 group 4 syn by 20%.

Rhett

 

[bepperb]

I have a Valvoline syn 5-30, conventional 5-30 and conventional 10-40. At around 30 it's hard to tell the difference. At 20 the 40 is obviously thicker, but the other two feel the same until about 0 degrees. This is the unscientific "shake the bottle" test. Maybe I need to upgrade to your funnel system. But, from what I feel you're still too warm. But also, the "straight 30" is probably more like a 15w-30. There are only markets for "straight 30" and 10w-30 and nothing in between, so if it barely misses the 10w test, well, it's a 30 weight.

 

[twigdog]

That's kinda what I've been thinking. Might be different in the freezer, but I don't drive in there and it's about as cold as it gets here. Single dijits are very rare.

Thanks

 

[Gary Allan]

Quote:
But, from what I feel you're still too warm.


Yes, he is ..but it demonstrates that the conceptual view of thick and thin are mostly bogus if you're using the "W"'s as some indication of how the oil should appear/react outside of those extreme cold temps.

 

[tig1]

I put a Qt of M1 5-30 and a qt of str. 30wt. dino, chain saw bar oil, in the freezer just now. will se the differance in that in 4 hours. Will be interesting to see the diff.

 

[twigdog]

Probably huge

 

[tig1]

Originally Posted By: tig1
I put a Qt of M1 5-30 and a qt of str. 30wt. dino, chain saw bar oil, in the freezer just now. will se the differance in that in 4 hours. Will be interesting to see the diff.


Today my wife says to me "Whats this oil doing in my freezer"? I totally forgot to get the oil out. The 30wt is a SM straight 30wt. oil which I use as bar lube for the chain saw, and wouldn't slosh at all, I mean like thick molasses. The M1 5-30EP was very fluid and sloshed easily. The temp was -2F in the freezer.
M1 15-50 has a pour point of -39C so I think something is not right with your test.
Maybe I will buy a qt. of 15-50 and try the same test myself that you did. I could use it in my mower next summer.

 

[twigdog]

Originally Posted By: tig1
Originally Posted By: tig1
I put a Qt of M1 5-30 and a qt of str. 30wt. dino, chain saw bar oil, in the freezer just now. will se the differance in that in 4 hours. Will be interesting to see the diff.


Today my wife says to me "Whats this oil doing in my freezer"? I totally forgot to get the oil out. The 30wt is a SM straight 30wt. oil which I use as bar lube for the chain saw, and wouldn't slosh at all, I mean like thick molasses. The M1 5-30EP was very fluid and sloshed easily. The temp was -2F in the freezer.
M1 15-50 has a pour point of -39C so I think something is not right with your test.
Maybe I will buy a qt. of 15-50 and try the same test myself that you did. I could use it in my mower next summer.



That's almost 30 degrees colder than what I was testing at. I didn't think to check the 5w30 maxlife I put in the wife's truck. This experiment was an afterthought when I was putting everything back up. Pour point on the Havoline 30w is -30c so not a big difference.