The labels on most cans of auto engine now – actually now in most cases plastic bottles – more than confuse most motorists. Which do you purchase and when? Do you spend more for that can or oil or oil change as the kid at the fast oil lane advises as part of his up scaling of your purchase? Come to think of it what did the tech service writer at the dealership where you bought the car advice? And is this all consistent with the automobile’s bible – the owner’s manual in the glove box?

Understanding motor oil types, their labels and descriptions is actually quite easy to comprehend. Motor engine oils are classified, labeled and standardized with a consistent and reasonably logical system. It all makes sense and ensures the correct product is available as required by your vehicle, service levels and overall driving conditions.

Engine oils are graded according to their thickness or viscosity by a respected industry professional standards group – “The Society of Automotive Engineers”.

In short form the Societies professional association name is shortened to its abbreviation “SAE”. Most likely you have seen the phrase and letters SAE on older metal oil cans and on the labels of newer types of plastic containers in which you purchase oil and to which are emptied to fill your engine crankcase.

Viscosity refers to oil’s resistance to flow. Oil that flows easily and lightly like say cooking oil is referred to as “Thin” oil whereas oil that flows slowly like molasses is termed “Thick” or “Heavy”. Oil is rated in its thickness or thinness with its comparative ability to flow easily. Oil viscosity has been given n oil viscosity index rating after thorough testing and evaluation by the S.A.E. that is the “Society of Automotive Engineers”. On top of that engine oil when heated typically and generally becomes thinner (flows more easily that is corresponding to a less viscous state). If specific oil thins out a great amount upon heating or warming, then it is said to have a Low VI (Viscosity Index). If it resists thinning on heat it will be said to have a high VI. This VI rating and ranking is both an indication and measurement of a given oils ability to resist viscosity changes brought on by heat, and in this case specifically engine heat and high temperatures.

Thus engine motor oils are graded and rated for use and specific usages according to their viscosity by the SAE (Society of Automotive Engineers) numbers ranging from typically 5 W to 50. This rating is actually determined commercially by a device called and referred to as a vicosimeter.

A specific amount of the oil to be tested is placed in this highly accurate Viscosimeter device and then brought up or down in temperature to an exact standardized measurement temp. The oil is then allowed to flow through and opening of definite measured diameter. The time in seconds, required for the sample to pass through determines the measured and awarded level of viscosity of that particular brand or type of motor engine oil. The higher the number (slower flow) the heavier (more viscous) is the oil.

Thus you need not be intimidated when asking your dealer technical service writer, the kid at the fast lube place or when purchasing oil at a big box auto store.

Oil generally comes now in blends, rather than single weights. Most commercial auto engine oils that you will come across in 2010 – 2011 are not one single weight for one season but are blended for good flow during cold winter times and hot temperatures either in the summer or for long extended freeway trips when your engine temperature will remain high and hot. The common blends involved are 5W30, 10W30, 10W30 & 5 W30 or 40. The letter designation “W” is a designation by the SAE that the oil is suitable and will flow in wintertime frigid temperature conditions.

Author Bio: Harold Z. Stofman Derrick Dodge Lowest Prices Highest Volume Dodge Chrysler dealership worldwide Canada High volume purchases means lowest prices for you Edmonton Dodge R/T 2010 Fort mcMuray Jeep Compass St Albert Alberta Jeep Compass 2010