“How Often Should I Change My Oil?”

You’ve probably heard the adage that engine oil should be changed every 3 months or 3,000 miles.  If you were driving a car or truck when that saying was popular, you know oil technology has grown a lot since then. Synthetics are far more popular, and it seems every major oil company now has a competitor in the market. While 3,000 miles or 3 months isn’t the benchmark target anymore, changing your oil at a particular frequency is still a requirement.  The question is why? Why do you still need to change your oil?  To answer “Why should I change my oil”, let’s explore below.

WHY Should I Change My Oil?   What Happens to Oil Over Time?

Engine oil, regardless of its additives, viscosity, and its base oils, ages over time. It loses its initial potency for protection, and the effectiveness to keep your engine running at peak performance. Why does this occur? These factors attribute to oil losing effectiveness:

  • Oxidation – Oxygen causes a chemical breakdown in oil, exposed metal, and organic materials. This chemical breakdown causes increased oil viscosity and a loss of effective protection for bearings and engine internal components. You will also see more deposits and engine sludge form over time due to excessive oil oxidation.
  • Excessive Heat – Engines run hot, even when they have proper cooling systems. Thirty years ago, engines were running in the 170-degree range, but today’s modern engines are running into the 235-degree ballpark. Oil oxidizes faster in higher heat and can double the oxidation rate for every 18°F (10°C) of temperature increase. That means towing and hauling can push your engine oil to extremes.
  • Moisture – As if the heat wasn’t enough, you have to worry about moisture attacking your oil too. Temperature swings, even when sitting in the garage, cause moisture to form inside your engine. Enough moisture causes condensation to build into droplets, and lead to water contamination of your engine oil. Oxidation, as well as moisture, can lead to that engine sludge. It’s a 1-2 combo that hurts oil performance.

How Can Oil Lose Viscosity if I don’t change my oil?

Viscosity plays a large part in keeping your engine well protected. Low viscosity oil flows very easily, while higher viscosity looks more like molasses. Your engine oil must fit into very small places to keep bearings lubricated, which means it must survive extreme pressure. That pressure can destroy its molecular structure, which leads to the oil losing viscosity. You could start with a 10W-40 oil after it’s been freshly changed, and it can end at a 10W-20 when it’s ready to be changed in thousands of miles.

The fuel you burn in the combustion chambers, whether it’s diesel or gasoline, can wash past your piston rings. When it gets past the rings, it washes your engine cylinders and contaminates the engine oil. That can also lose viscosity with the oil. You need to get the engine to operating temperature to ensure the fuel volatilizes correctly and burns completely. If you only make short trips, you may not allow the engine to fully warm up. That can also cause the fuel to contaminate the engine oil.

Answering "Why should I change my oil".

Why Additives in Your Oil Matter

Engine oils contain additives. Certain additives are detergents that clean out the varnish and sludge that forms over time. Others are antioxidants that keep oxidation from occurring.  Their properties enhance the base oils to add extra protection and function. Most additives are meant to be used over the life of the oil, which means they are depleted with use. When the oil is ready to be changed, the additives are most likely used up. Changing the engine oil replenishes the protection needed to keep your engine running smooth.

No matter what viscosity your engine requires, AMSOIL will have you covered. Today’s synthetic engine oils reduce thermal runaway, prevent corrosion, and keep your engine clean. If you need help with determining a complete maintenance plan for your vehicle, your local AMSOIL dealer at Buy Great Oil is here to help with a complete package of products and hints to make the job easier and more cost-effective.

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