Leave it to TallPaul to bring up the grinding compound guy....everytime!
5W-30 + 10W-30= 7.5W -30?
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Yes,,,Just like mixing green Castrol with gold Castrol will cause a terrible color clash.Really bad!!
Just don't mix up a brew using Pennzoil. You'll get twice the amount of sludge.
I was thinking of adding 1.5 qts of Mobil 1 5w30
to the remaining 3 quarts of Mobil 1 0w30 that I have left for the winter OCI. Is it safe for me to assume that I'll have somewhat better cold weather properties than a 5w30 but not quite as good as if I used all 0w30?
to the remaining 3 quarts of Mobil 1 0w30 that I have left for the winter OCI. Is it safe for me to assume that I'll have somewhat better cold weather properties than a 5w30 but not quite as good as if I used all 0w30?
You should be fine. Your assumption is probably correct, although as a practical matter, I think you'd be hard pressed to define any real functional boundary between a pure fill of 0w-30 and the soup that you're proposing. The 5w-30 itself is a great cold weather oil in its own right. It's not as if you're dumping a couple qts of straight 60 wt into your 0w-30, afterall.
How come nobody has come up with the obvious?
THERE IS NO SUCH THING AS 7.5W OIL! THE NUMBERS DON'T REPRESENT ANY LINEAR SCALE PER SE. THEY REPRESENT A RANGE OF VISCOSITY.
The early number represents the oil meets certain cold cranking/pumping capabilities. If it's too thick to be considered a 5W oil, it will be labelled as a 10W oil. It's like boxing categories - like lightweight, middleweight, or heavyweight. If you miss one, you go up to the next level.
http://www.infineum.com/information/api-viscosity-2004.html
So the answer to the original poster's question is:
It depends on a lot of factors that can't be simply answered with the information you've given. Oil viscosities represent a range. 30 weight at 100°C actually means a range of allowable viscosities from 9.3 to 12.5 cSt. I wouldn't worry too much about mixing most 5W-30 with 10W-30. In all likelihood you'll end up with something meets either the 5W-30 or 10W-30 requirements.
THERE IS NO SUCH THING AS 7.5W OIL! THE NUMBERS DON'T REPRESENT ANY LINEAR SCALE PER SE. THEY REPRESENT A RANGE OF VISCOSITY.
The early number represents the oil meets certain cold cranking/pumping capabilities. If it's too thick to be considered a 5W oil, it will be labelled as a 10W oil. It's like boxing categories - like lightweight, middleweight, or heavyweight. If you miss one, you go up to the next level.
http://www.infineum.com/information/api-viscosity-2004.html
So the answer to the original poster's question is:
It depends on a lot of factors that can't be simply answered with the information you've given. Oil viscosities represent a range. 30 weight at 100°C actually means a range of allowable viscosities from 9.3 to 12.5 cSt. I wouldn't worry too much about mixing most 5W-30 with 10W-30. In all likelihood you'll end up with something meets either the 5W-30 or 10W-30 requirements.
Y_P_W said
[ October 12, 2005, 01:43 AM: Message edited by: theguru ]
Maybe I should contact the dealer and tell him the oil he sells doesn't exist. It is a Nissan and Nismo specified oil. It exists, maybe not in SAE land. Plenty of references to it if you do a google search.
[ October 12, 2005, 01:43 AM: Message edited by: theguru ]
Just tell him it's falsly labeled.
ypw - Flyweight, welterweight, and light-heavyweight are all legitimate categories, as well.
I didn't want to get that specific at the time. That would only have lead to bringing up obscure weight classifications such as bantamweight or cruiserweight. And what the heck does "super flyweight" mean?
I think a clearer description would be of automative weight classifications, like sub-compact, compact, intermediate, or large.
0W/5W/10W/15W/20W were more or less arbitrary ranges. While someone could conceivably market a "7.5W-30" oil, it certainly wouldn't be compliant with the SAE J-300 spec for labelling oil.
5W30 + 10W30 = 15W60 !! Your cars going to blow !!!
I googled the 7.5W.
I found references to sites in Oz, Korea and Russia. Also a Nissan Skyline site. Interesting.
Makes me think of Royal Purple's "3W-30" marketing gimmick.
Anyway, regarding the guy saying the oils would separate because one has a base oil with 5W and the other has a base oil of 10W... bologna.
Multi-weight oils can have varying "base" oil viscosities. One 10W30 I'm aware of is actually a straight 20 weight with pour point depressants and additives to increase its high-temp viscosity.
Bear in mind that while some oils may very well blend to half-way between 5W and 10W, depending on additives in play, you may wind up with different viscosities than you'd imagine.
I saw a tribologist on usenet discussing formulations one time, and he mentioned a 5W30 from one vendor which, when mixed with another vendor's 10W30, would produce a 15W40 due to a weird additive reaction.
I found references to sites in Oz, Korea and Russia. Also a Nissan Skyline site. Interesting.
Makes me think of Royal Purple's "3W-30" marketing gimmick.
Anyway, regarding the guy saying the oils would separate because one has a base oil with 5W and the other has a base oil of 10W... bologna.
Multi-weight oils can have varying "base" oil viscosities. One 10W30 I'm aware of is actually a straight 20 weight with pour point depressants and additives to increase its high-temp viscosity.
Bear in mind that while some oils may very well blend to half-way between 5W and 10W, depending on additives in play, you may wind up with different viscosities than you'd imagine.
I saw a tribologist on usenet discussing formulations one time, and he mentioned a 5W30 from one vendor which, when mixed with another vendor's 10W30, would produce a 15W40 due to a weird additive reaction.
Thanks for the information, advice, and chemistry lesson. It looks like it would be best if I did not "cross-blend" different brands.
I had been tinkering with a blend of Mobil and Valvoline which gave me "Mobiline". Havoline and Formula Shell gave me "Hav-****" . However, I got very worried when I mixed Castrol and Quaker State and ended up with "Castrate". Then I knew that I was in way too deep . . .
I had been tinkering with a blend of Mobil and Valvoline which gave me "Mobiline". Havoline and Formula Shell gave me "Hav-****" . However, I got very worried when I mixed Castrol and Quaker State and ended up with "Castrate". Then I knew that I was in way too deep . . .
In my non-experience days, I mixed Vavoline Durablend, Castrol, and Redline with a Fram filter. Needless to say that what I got was "Endoftheline".
The base oil of a 10w-30 is compared to a 5w-30 denser, of larger molecules, higher viscosity. However you want to say it the 10w-30 is heavier than the 5w-30 at less than operating temperatures.
This is why oil floats on water. It is less dense than water. The 5w will "float" on top of the 10w. Larger molecules sink to the bottom.
This will occur until the oil pump mixes the oil, however when the car is shut off the 10w being denser will "sink" the 5w being lighter will "float". I have tried to make this a simple as possible.
You will not have a 7.5w-30!!!!!!!!!!!!!!!
This is why oil floats on water. It is less dense than water. The 5w will "float" on top of the 10w. Larger molecules sink to the bottom.
This will occur until the oil pump mixes the oil, however when the car is shut off the 10w being denser will "sink" the 5w being lighter will "float". I have tried to make this a simple as possible.
You will not have a 7.5w-30!!!!!!!!!!!!!!!
A 5W-30 or a 10W-30 is blended from 2 or more base oils that combine to form a single viscosity.
This blend of base oils does not separate or settle out, either in the oil bottle/jug or in a engine crankcase.
Nice try, Camu, but I hope you are better at Lara Croft than whatever game you are trying to play here!
This blend of base oils does not separate or settle out, either in the oil bottle/jug or in a engine crankcase.
Nice try, Camu, but I hope you are better at Lara Croft than whatever game you are trying to play here!
WRONG ALL common base stocks will mix and stay mixed with each other. They DO not seperate in the bottle or the sump.
MOST all PCMO's are a blend of various vis grades of base oil.
Example:
A 5/30 may have both 100N and 240N base oil.
A 40wt may have a 600N and 150 bright stock.
They all stay mixed and in fact some base oils sold are a blend of a heavier and thinner lube stock.
Density's are so close and solubility so good that they do not seperate SIMPLE.
bruce
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