For the beginning mechanic, few things are as misunderstood as engine oil. There are so many misconceptions out there about engine oil that it's no surprise. You've probably heard many of these falsehoods so often that they just seem true. Here's a look at a few things that you should know about oil and these common misconceptions.
The "W" Rating Isn't For Weight
Because the viscosity rating of oil is sometimes referred to as its weight, many people believe that the "W" found in engine oil labels, like 15W-30 oil, means "weight." In fact, the "W" on this label actually refers to winter. Remember that engine oil's viscosity changes based on temperature. The warmer the oil, the less viscous it is. The "30" refers to the basic viscosity of the oil, which is the same as you'd find in single-grade oils that are just labeled with one number, like SAE 40. The lower number that's followed by the "W" actually defines the viscosity of the oil when it's subjected to cold temperatures like those of winter.
Synthetic Oil Doesn't Damage Your Engine
When synthetic oils first hit the market, the formulation of the oil didn't react well to gaskets and other hardware that had been exposed to petroleum-based oil all along. As a result, it would damage the gasket and lead to oil leaks after making the synthetic oil switch. This led to lasting rumors and misconceptions about the formulas leading to oil leaks, gasket damage, and other engine problems. The truth is that synthetic oil functions through your engine the same way that a conventional oil does. Despite the roadblocks of the initial formulation, synthetic oils have been redesigned to be easier on your car's engine and components, reducing the chances of this type of problem.
You Don't Need Oil Additives
If you have heard that engine oil additives can help improve the engine oil flow and preserve the integrity of the system, that part is true. However, if you've heard that you have to put these additives in to protect your engine oil, this isn't the case. Most modern engine oils now come with many of these additives already in them because the oil manufacturers recognize the benefit of them as well.
For more information or to choose a new oil for your car, talk with your local engine oil supplier, auto parts store, or mechanic. He or she can help you. You may also want to check out a website such as http://www.smallandsonsoil.com.