5w-50 Synthetic Oil
Administrator
Joined: Nov 1998
Posts: 71,097
From: Hell was full so they sent me to NJ
Huge waste of power to drive the pump, so thick its probably not going to circulate properly, and the added load on the oil pump drive could prove to be a problem with the plastic used on the drive support.
Registered User
Joined: Mar 2008
Posts: 56
From: Walkerton ON Canada
Your a little backwards there. its 5 when you warm up and 50 when you start, (80w-90 is gear oil and 10w-30 is motor oil), a lower number is runnier. I dont see why you would run a w50 oil, everything I've ever used runs 10w30 or 5w30. You would have a lot oil pressure at start up and then the same as 5w30 once at operating temp
Registered User
Joined: Aug 2007
Posts: 316
From: Purgatory... Also known as New Jersey.
The multi-viscosity numbers are cold viscosity - hot viscosity.
Use your head; why the hell would you want oil to be like jello when it's cold and water when it's hot?
Look here:
http://auto.howstuffworks.com/question164.htm
http://auto.howstuffworks.com/framed...nfo/oiled.html
Here's the pertinent paragraph:
Multi-weight oils (such as 10W-30) are a new invention made possible by adding polymers to oil. The polymers allow the oil to have different weights at different temperatures. The first number indicates the viscosity of the oil at a cold temperature, while the second number indicates the viscosity at operating temperature. This page from the Sci.Electronics.Repair FAQ offers the following very interesting description of how the polymers work:
At cold temperatures, the polymers are coiled up and allow the oil to flow as their low numbers indicate. As the oil warms up, the polymers begin to unwind into long chains that prevent the oil from thinning as much as it normally would. The result is that at 100 degrees C, the oil has thinned only as much as the higher viscosity number indicates. Another way of looking at multi-vis oils is to think of a 20W-50 as a 20 weight oil that will not thin more than a 50 weight would when hot.
Use your head; why the hell would you want oil to be like jello when it's cold and water when it's hot?
Look here:
http://auto.howstuffworks.com/question164.htm
http://auto.howstuffworks.com/framed...nfo/oiled.html
Here's the pertinent paragraph:
Multi-weight oils (such as 10W-30) are a new invention made possible by adding polymers to oil. The polymers allow the oil to have different weights at different temperatures. The first number indicates the viscosity of the oil at a cold temperature, while the second number indicates the viscosity at operating temperature. This page from the Sci.Electronics.Repair FAQ offers the following very interesting description of how the polymers work:
At cold temperatures, the polymers are coiled up and allow the oil to flow as their low numbers indicate. As the oil warms up, the polymers begin to unwind into long chains that prevent the oil from thinning as much as it normally would. The result is that at 100 degrees C, the oil has thinned only as much as the higher viscosity number indicates. Another way of looking at multi-vis oils is to think of a 20W-50 as a 20 weight oil that will not thin more than a 50 weight would when hot.
Registered User
Joined: Jun 2006
Posts: 2,092
From: lakeville, pa
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Registered User
Joined: Aug 2007
Posts: 316
From: Purgatory... Also known as New Jersey.
Yes, that must be the answer. The whole world is conspiring to hide the fact that the oil viscosity numbers are BACKWARDS! It's thicker when cold! Those tricky, deceiving BASTARDS!
Or, Dangalla is wrong.
What do you think is more likely?
Did it ever occur to you that the oil is thinner when hot because it's... I don't know... What's the word I'm looking for... hot? How about any oil of a given viscosity is thicker when cold and thinner when hot? A 10 weight oil when cold will be thicker than it will when hot. A 50 weight oil will be thinned out when it's hot and will have all the flow characteristics of jello when cold. But a 50 weight oil, hot, will still have a higher viscosity rating than the 10 weight oil. Which is why the oil companies use additives to alter the oil's viscosity ratings based on temperature. It's a 0 weight oil when cold, so it'll flow. It acts like a 50 weight when hot, so you still have the hydrostatic wedge keeping your metal bits from meeting with each other.
Or, Dangalla is wrong.
What do you think is more likely?
Did it ever occur to you that the oil is thinner when hot because it's... I don't know... What's the word I'm looking for... hot? How about any oil of a given viscosity is thicker when cold and thinner when hot? A 10 weight oil when cold will be thicker than it will when hot. A 50 weight oil will be thinned out when it's hot and will have all the flow characteristics of jello when cold. But a 50 weight oil, hot, will still have a higher viscosity rating than the 10 weight oil. Which is why the oil companies use additives to alter the oil's viscosity ratings based on temperature. It's a 0 weight oil when cold, so it'll flow. It acts like a 50 weight when hot, so you still have the hydrostatic wedge keeping your metal bits from meeting with each other.
Registered User
Joined: Jan 2008
Posts: 466
From: Cypress, TX
Let me try.
You basically have two different viscosities of oil: 5 and 50 "weight".
When your vehicle has been sitting overnight and you jump into it in the
morning, insert the key, and go to crank the motor . . . when the motor fires
up, the thinner (5wt) viscosity oil immediately circulates about the engine,
providing protection to all engine components. (because it's thinner and
will circulate immediately).
This is a good thing if you live in a "predominately" cold area (such as in the
Northern US).
So, what about the 50w? Well, the 50w is good if you have a high-revving
engine or live in high-temperature areas, such as the deep-South of the US.
(I do - in south Texas . . . temps can average 100+ in the summer). So,
possibly, if you live in the deep South in the summer with soaring temps
and you're hard on your engine, then 50w would be good (well, maybe not).
Why? Because the HEAT will break down the oil's properties and it will
begin to "break down" (or shear away from itself). In this situation, you
want an oil that will continue to "bind together".
My perspective? I think 50 weight is over-rated. I ride a 99 Hayabusa that
I bought brand new that puts out 205 HP and I ride it in the dead of summer
and run it HARD. And I dont use 50w in it - I use Motul 40w Synth all year
round. And I dont run any oils with a weight greater than 40w in all of my
other vehicles.
I think the important question to ask (I might have already) is, "why do you
feel you need to run 50w oil" ???
You basically have two different viscosities of oil: 5 and 50 "weight".
When your vehicle has been sitting overnight and you jump into it in the
morning, insert the key, and go to crank the motor . . . when the motor fires
up, the thinner (5wt) viscosity oil immediately circulates about the engine,
providing protection to all engine components. (because it's thinner and
will circulate immediately).
This is a good thing if you live in a "predominately" cold area (such as in the
Northern US).
So, what about the 50w? Well, the 50w is good if you have a high-revving
engine or live in high-temperature areas, such as the deep-South of the US.
(I do - in south Texas . . . temps can average 100+ in the summer). So,
possibly, if you live in the deep South in the summer with soaring temps
and you're hard on your engine, then 50w would be good (well, maybe not).
Why? Because the HEAT will break down the oil's properties and it will
begin to "break down" (or shear away from itself). In this situation, you
want an oil that will continue to "bind together".
My perspective? I think 50 weight is over-rated. I ride a 99 Hayabusa that
I bought brand new that puts out 205 HP and I ride it in the dead of summer
and run it HARD. And I dont use 50w in it - I use Motul 40w Synth all year
round. And I dont run any oils with a weight greater than 40w in all of my
other vehicles.
I think the important question to ask (I might have already) is, "why do you
feel you need to run 50w oil" ???
