Post by papaya on Jul 25, 2005 9:25:54 GMT 10
Came across this article on the internet... Very useful for novice like myself...
Motor Oils
Most people recognize motor oils by their multi viscosity rating. Viscosity refers to the thickness, or flowabiltiy of an oil. Generally, thicker oil means higher viscosity and better protection at higher temperatures, and thinner oil means lower viscosity and better protection at lower temperatures (especially at startup).
The multi in multi viscosity refers to an oil engineered to flow at the lower viscosity rating (eg.the 5 in 5w30) when cold, but perform at the higher viscosity rating (the 30 in 5w30) when hot. The w indicates that the oil is suitable for winter use.
Synthetic lubricants posess a host of improvements over petroleum based lubricants, with little to no drawbacks. Synthetics provide a much more effective protection within a wider range of temperatures, and do not break down as fast as petroleum based oils. Synthetic oils are laboratory produced at a molecular level, so that they contain only what they are meant to contain, with no contaminants. Petroleum based lubricants are derived from crude oil, and even though they are highly refined, they will always contain significant amounts of contaminants. For this reason, just adding a synthetic additive to petroleum based oil will not have the same effects as using a full synthetic.
There are basically only two situations when synthetic oils should not be used in an engine. The first is on a brand new or just re-built engine. Synthetics provide such a high degree of wear protection that they will not allow a new engine to properly break-in. Synthetics can be used on new or re-built engines after the break-in period. The second situation is when an engine already leaks or consumes a significant amount of oil. This is due to the high cost of constantly replacing the oil and the fact that an engine in this state of tune may need to be repaired or re-built anyway.
Motor Oils
Most people recognize motor oils by their multi viscosity rating. Viscosity refers to the thickness, or flowabiltiy of an oil. Generally, thicker oil means higher viscosity and better protection at higher temperatures, and thinner oil means lower viscosity and better protection at lower temperatures (especially at startup).
The multi in multi viscosity refers to an oil engineered to flow at the lower viscosity rating (eg.the 5 in 5w30) when cold, but perform at the higher viscosity rating (the 30 in 5w30) when hot. The w indicates that the oil is suitable for winter use.
Synthetic lubricants posess a host of improvements over petroleum based lubricants, with little to no drawbacks. Synthetics provide a much more effective protection within a wider range of temperatures, and do not break down as fast as petroleum based oils. Synthetic oils are laboratory produced at a molecular level, so that they contain only what they are meant to contain, with no contaminants. Petroleum based lubricants are derived from crude oil, and even though they are highly refined, they will always contain significant amounts of contaminants. For this reason, just adding a synthetic additive to petroleum based oil will not have the same effects as using a full synthetic.
There are basically only two situations when synthetic oils should not be used in an engine. The first is on a brand new or just re-built engine. Synthetics provide such a high degree of wear protection that they will not allow a new engine to properly break-in. Synthetics can be used on new or re-built engines after the break-in period. The second situation is when an engine already leaks or consumes a significant amount of oil. This is due to the high cost of constantly replacing the oil and the fact that an engine in this state of tune may need to be repaired or re-built anyway.
