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Why Motor Oil Deteriorates

Why Motor Oil Deteriorates

 

Like just about everything else, motor oil has a lifespan. Even the best oils eventually require you to change them. Historically, many motorists like the convenience of changing oil with the seasons, visiting the quick lube or pulling the ramps out of their garage each spring and fall.

Motor oil can deteriorate by becoming contaminated, the additives depleting over time or both.

How oil becomes contaminated

Base oils are the backbone of the finished lubricant that ends up in your engine. They can be conventional, synthetic or a combination thereof. They’re responsible for lubricating components, which reduces friction and protects against wear.

Base oils can lose their effectiveness over time due to a few different factors.

Oxidation – The interaction between oxygen molecules and motor oil molecules naturally leads to chemical breakdown. Just as oxygen causes a cut apple to brown or exposed metal to rust, it breaks down base oils and reduces motor oil’s effectiveness. Oxidation can lead to increased oil viscosity, which negatively affects energy efficiency. It also causes the formation of harmful deposits and sludge.

High heat – Today’s engines run hotter than ever before, with temperatures up to 235°F, and even higher if towing or hauling. The rate of oxidation for oil doubles for every 18°F increase in temperature.

Moisture – Your vehicle is also subjected to temperature swings, even when it is parked in the garage. Those temperature swings cause condensation to form inside your engine, leading to water contamination. Leaving a vehicle parked for extended periods or taking short trips that don’t allow the engine to fully warm up allow water to remain in the oil rather than evaporating and exiting through the tailpipe. Water can lead to formation of sludge.

Viscosity loss – A lubricant’s viscosity is its most important property. Viscosity has a direct bearing on wear protection, and your engine is designed to operate best using a motor oil of a specific viscosity (e.g. 5W-30). The intense pressure the oil bears as it’s squeezed between moving parts, like the piston ring/cylinder wall interface, can tear apart, or shear, its molecular structure, leading to viscosity loss. Suddenly, the 5W-30 motor oil your engine was designed to use is now essentially a 5W-20 oil, and wear protection may be compromised.

Fuel dilution – Fuel can wash past the piston rings and contaminate the motor oil, causing it to lose viscosity. Frequent short trips that don’t allow the oil to reach normal operating temperature can be especially problematic because the fuel won’t volatilize and exit through the PCV system. Excessive fuel dilution leads to sludge and varnish, requiring the oil to be changed more often.

Additive are designed to deplete

Additives are added to base oils to reduce destructive processes and enhance beneficial properties. For example, antioxidant additives help slow the rate of oxidation. Detergency additives help prevent deposits and sludge while cleaning pre-existing deposits. Anti-wear additives are added to some lubricants to form a sacrificial barrier on metal components and help prevent wear.

Since they’re sacrificial in nature, additive depletion is one of the primary reasons motor oil loses its effectiveness and must be changed.

Though all motor oils eventually deteriorate, synthetic oils last longer than conventional oils and deliver improved protection against wear and deposits. They’re formulated with base oils that are more resilient to oxidation and heat, while their additives also typically offer improved performance.

In fact, AMSOIL Signature Series Synthetic Motor Oil performs so well you can go up to 25,000 miles/one year between oil changes (15,000 miles/one year in severe service) if you want, saving money.

Al Amatuzio: A Heart of Gold

Al Amatuzio: A Heart of Gold

To say AMSOIL founder Al Amatuzio leaves behind a legacy is an understatement. He created the first synthetic motor oil in the world to meet American Petroleum Institute (API) service requirements, fathered a beautiful family, built an AMSOIL family of dedicated employees and independent Dealers, and supported numerous causes through his philanthropic ways.

Al loved the Duluth/Superior community. He grew up here and built his life within this close-knit community. Despite numerous offers to relocate the AMSOIL business out of this community, Al remained loyal to his roots.

While Al had many passions, he held a few near and dear to his heart. We’d like to share them with you here.

AMSOIL Northland Law Enforcement K-9 Foundation

Al always had a special place in his heart for dogs and was particularly fond of German Shepards, which are a fixture in many police departments. The Northland K-9 Foundation was created to support the law enforcement K-9 programs of the Duluth, Hermantown, Minn., and Superior Police Departments, and the Douglas and St. Louis County Sheriff’s Offices. “He would tell us if we needed a dog to call him,” said Duluth Police Chief Mike Tusken. “He would outright pay for them, and it was multiple dogs. He was a great man and tremendous benefactor to this community.”

 

 Animal Allies

Animal Allies Humane Society strives to ensure a lifetime of loving care for every pet by reducing overpopulation, increasing adoption and fostering humane values. They are guided by a humane ethic to build communities that universally value animals, understand their needs and take action to meet them.

Animal Allies presented this photo to Al as a token of their appreciation, and it proudly hangs above one of our drinking fountains at the Corporate Office here in Superior.

Douglas County Humane Society

The Douglas County Humane Society is dedicated to preventing cruelty to animals, relieving suffering among animals and promoting humane education. The Society provides shelter, medical care and adoption services to abandoned, lost and misplaced animals. They provide services for approximately 1,000 animals each year from the City of Superior and Douglas County.

Boys & Girls Club

The Boys & Girls Clubs of the Northland is dedicated to ensuring that our community’s youth have greater access to quality programs and services that empower their lives and build great futures. Their mission is to enable all young people, especially those who need us most, to reach their full potential as productive, caring, responsible citizens.

Albert J. Amatuzio Research Center

Located in the Duluth Depot, the Albert J. Amatuzio Research Center chronicles local service history dating back to the Civil War. This research center includes photographs, journals, stories and biographies of veterans from northeastern Minnesota who served this nation from the Civil War through Iraq and Afghanistan.

Al began to build his legacy as a proud member of both the Merchant Marine and the U.S. Air Force. He served 25 years as a fighter pilot and squadron commander with the Air National Guard out of Duluth, Minn.  Al, nicknamed “Ammo” by his fellow pilots, was twice honored as our nation’s top pilot.

 

 

 

 

 

 

The passion behind Al’s philanthropic history will live on in the Twin Ports and in the hearts of everyone whose life he changed.

Read more about what AMSOIL employees and AMSOIL Dealers had to say about their fearless and lovable leader.