Oil is the lifeblood of your engine. It reduces friction, lessens wear, provides lubrication, forms a seal between the pistons, rings and cylinder walls while helping to cool engine parts. Without the cleaning action of new oil, carbon and varnish buildup would be toxic to the engine. And engine oil even dampens the shock and noise of moving parts.
Most cars on the road today use multi-grade oil — one that can work efficiently in cold and hot weather. A multi-grade oil is rated by two numbers.
About the oil classification system.
Each engine oil comes with a classification indicating its viscosity, which is its friction or resistance to flow. In a multi-grade oil, the first number indicates how the oil will flow when it is cold. The lower the number, the lighter the oil and the better it will perform at lower temperatures.
Why viscosity is a concern.
During cold starting, only a small amount of oil is present in the upper parts of engines. To lessen the friction when upper engine parts, such as the valve train, pistons, overhead cam and cam bearings, scrub against each other, a lower viscosity allows the oil to reach the components more quickly.
Automatic Transmission Fluid
This is typically an oil-based fluid used in a transmission that lubricates and cools the transmission and provides hydraulic pressure to shift gears automatically.
Why 5W-30 and 5w-20 oils are so popular.
Many vehicles today leave the factory with 5W-30 or 5w-20 engine oil. Vehicle manufacturers recommend them because they are lighter oils that perform well in a range of temperatures and help improve gas mileage.
Which oil is right for your car?
The simplest and safest way to find out is to check your owner’s manual...or talk to your Midas mechanic.
Your vehicle relies on a variety of fluids to operate its brake, steering, transmission, engine cooling and other systems. When these fluids become degraded or are at incorrect levels, damage to other components may occur...so always follow the manufacturer.