It is common knowledge that, at some point, engine oil must be changed. It's something that is preached relentlessly to vehicle owners by vehicle manufacturers, quick lubes and oil companies. But consumers may be unaware of what exactly makes oil changes necessary.
Many factors contribute to a motor oil's demise, but it is essentially the accumulation of contaminants in the oil and chemical changes in the oil itself that make a motor oil unfit for further service. With time, it is inevitable that the oil will be contaminated by dirt or sludge, or succumb to the extreme pressures and temperatures found inside an engine. The Lube Dudes uses only the highest quality motor oils that have been formulated and tested to meet or exceed the manufacturer’s specifications for your vehicle.
Extreme Heat
Today's engines are running hotter than ever. More horsepower,
turbo chargers and aerodynamic styling have created extremely
hot environments that receive less cooling from outside
air. High heat leads to oil oxidation, deposits and thickening
in oils.
Even in relatively mild temperatures, oxygen works to break down some of the chemicals in lubricants. The extreme heat in engines actually promotes oxidation. When oil contaminants break down, they coat components with varnish, deposits and sludge and leave the lubricant thick, hard to pump and with very poor heat transfer ability.
Common Contaminants
Dust and dirt from the air enter the engine through
faulty air cleaners, some oil fill caps and crankcase ventilation
systems. Normal engine wear produces small metal particles
that are picked up and circulated by the oil. The abrasive
particles of road dust and dirt increase the rate of wear
and generate larger metal particles. Those particles are
equally abrasive and the rate of wear accelerates with
a snowball effect. While filtration removes most of these
contaminants, some remain and are left to circulate with
the oil.
Combustion By-Products
Combustion produces several byproducts that also act as contaminants.
Water and acids lead to sludge, rust and corrosion. Soot
and carbon create sludge and varnish and can clog filters.
Unburned fuel in liquid form is deposited on cylinder walls
where it leaks past the rings into the crankcase. Sludge
deposits collect on oil pump screens, limiting the flow
of oil to vital engine parts and resulting in rapid and
destructive wear. When oil becomes contaminated, its viscosity
changes. With soot, dirt, oxidation or sludge, viscosity
increases; with fuel dilution it decreases.
Internal Forces
Engines create a great deal of internal pressure. Extreme
pressure can result in boundary lubrication which breaks
the oil film between moving parts. Movement inside the
engine agitates the fluid, trapping air and forming bubbles
or foam. Because air is compressible, the ability of the
fluid film to prevent contact is reduced. And because the
mixed air contains oxygen, it promotes oil oxidation.
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