Oil Wars, Revisited!!!
02-20-2008, 12:45 PM
#92
Yeah, I figured I would ask the question in a straightforward way. But not really expecting a rational answer. More like some psychotic assertion that implies he knows more than god.
02-20-2008, 08:24 PM
#95
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I'm getting my oil changed tomorrow. Porsche recommends 0w40, and 5w40. I figure since I don't drive my car as much as I should, 5w40 will be a better lubricant during cold starts. When the car warms up to operating temps, the first number means nothing and the 40 kicks in, same as 0w40, right?
So, it looks like 5w40 will be my oil (and Porsche's) of choice!
So, it looks like 5w40 will be my oil (and Porsche's) of choice!
02-20-2008, 10:07 PM
#96
Burning Brakes
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I'm getting my oil changed tomorrow. Porsche recommends 0w40, and 5w40. I figure since I don't drive my car as much as I should, 5w40 will be a better lubricant during cold starts. When the car warms up to operating temps, the first number means nothing and the 40 kicks in, same as 0w40, right?
So, it looks like 5w40 will be my oil (and Porsche's) of choice!
So, it looks like 5w40 will be my oil (and Porsche's) of choice!
02-20-2008, 10:13 PM
#97
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Hmmm, I thought thicker oil protects better. Guess I'm wrong. Why do people call 0w40 Mobile water?
02-20-2008, 10:34 PM
#98
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The W in the viscosity stands for "winter." When the engine is cold, a single viscosity oil (say, 30 weight) would be way too thick when cold to be pumped effectively by the oil pump, and would take too long to enter tight tolerance areas. The upper sections of the engine would also be oil starved, and excessive wear would result. The only reason for multiple viscosity oils is to provide protection when the engine is first started and is cold.
02-20-2008, 11:02 PM
#100
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02-20-2008, 11:27 PM
#101
Race Car
02-20-2008, 11:34 PM
#102
It is time to dispel the notion that 0W-30 oil is too thin when our manual calls for 10W-30. A 0W-30 is always the better choice, always. The 0W-30 is not thinner. It is the same thickness as the 10W-30 at operating temperatures. The difference is when you turn your engine off for the night. Both oils thicken over the evening and night. They both had a thickness, a viscosity of 10 when you got home and turned your engine off. That was the perfect thickness for engine operation.
02-20-2008, 11:39 PM
#103
The W in the viscosity stands for "winter." When the engine is cold, a single viscosity oil (say, 30 weight) would be way too thick when cold to be pumped effectively by the oil pump, and would take too long to enter tight tolerance areas. The upper sections of the engine would also be oil starved, and excessive wear would result. The only reason for multiple viscosity oils is to provide protection when the engine is first started and is cold.
From SAE J300 p.2:
"Two series of viscosity grades are defined in Table (1): (a) those containing the letter W and (b) those without. Single viscosity grade oils with the letter W are defined by maximum low temperature cranking and pumping viscosities and a minimum kinematic viscosity at 100C. Single grade oils without the letter W are based on a set of minimum and maximum kinematic viscosities at 100C and a minimum high shear rate viscosity at 150C. The shear rate will depend on the test method. Multigrade grade oils are defined by both of these criteria....
The W is just a designation of one type of testing vs another. I personally asked them if it stood for "winter" and they flatly said "no".
"Two series of viscosity grades are defined in Table (1): (a) those containing the letter W and (b) those without. Single viscosity grade oils with the letter W are defined by maximum low temperature cranking and pumping viscosities and a minimum kinematic viscosity at 100C. Single grade oils without the letter W are based on a set of minimum and maximum kinematic viscosities at 100C and a minimum high shear rate viscosity at 150C. The shear rate will depend on the test method. Multigrade grade oils are defined by both of these criteria....
The W is just a designation of one type of testing vs another. I personally asked them if it stood for "winter" and they flatly said "no".
02-21-2008, 09:54 AM
#104
Race Car
hmmmmm
02-21-2008, 11:15 AM
#105
...I guess that makes it right...someone reads a post on here and thinks it is fact...next thing you know it is published in books (please post the reference)
YOU really should read the link.