The Need To Do Regular Oil Changes

Why Do I Need To Change My Oil?

Dan McClellandDan McClelland | Jan 07, 2020 8:36 AM




Regardless of its quality, every motor oil eventually loses its potency and must be changed to ensure peak engine protection. Let’s take a look at what happens to motor oil over time and why you periodically need to change oil.

Losing the base

Base oils are the backbone of the finished lubricant that ends up in your engine. Over time, they lose effectiveness due to the following 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 (113ºC), and even higher if towing or hauling.

The rate of oxidation for oil doubles for every 18°F (10°C) increase in temperature.

Moisture

Your vehicle is 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…yet another reason why you must change oil.

Viscosity is a motor oil’s most important property. The lower the viscosity, the faster the oils flows, like water. Thicker oils flow more slowly, like honey.

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. When this happens, it’s time to change your oil.

Shop AMSOIL Synthetic Motor Oil

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 you to change oil more frequently.

Additives: 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. Formulators add anti-wear additives 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. 

While AMSOIL synthetic motor oil gives you the convenience of fitting oil changes into your schedule, it remains vital to install fresh oil at the appropriate time.  

Shop AMSOIL Synthetic Motor Oil

Motor Oil Viscosity Explained

OE 0W-20 Now Available in Gallons

AMSOIL OE 0W-20 Synthetic Motor Oil (OEZ) is now available in gallon containers.

Premium Protection for High-Horsepower Ford Mustangs

5W-50 Synthetic Motor Oil

AMSOIL Signature Series 5W-50 Synthetic Motor Oil

AMSOIL has expanded the Signature Series line to include a robust 5W-50 synthetic motor oil formulated specifically for high-horsepower Ford Mustang engines. Signature Series 5W-50 Synthetic Motor Oil (AMR) provides top-of-the-mark protection and performance that customers expect from Signature Series, and it is excellent for all Mustang engines calling for a 5W-50 viscosity.

For more information:

AMSOIL Signature Series 5W-50 Synthetic Motor Oil for High-Horsepower Ford Mustangs

Quality filtration is equally as important as quality lubrication.

Mark Nyholm-  Technical Product Manager

Filters are often overlooked, but they are integral to keeping oil clean and performing at its best.

It’s often said that motor oil is the lifeblood of the engine. We depend on it to prevent wear, maintain cleanliness, minimize operating temperature and act as a seal. Should the oil become contaminated, its ability to perform these tasks can be greatly impaired. Dirty oil can cause piston ring wear, leading to increased oil consumption, and it can also accelerate wear in bearings and cylinders. Engine contaminants cannot be eliminated, but they can be controlled with proper filtration. Proper filtration helps keep oil clean and flowing freely, ensuring the lubricant will be able to perform its necessary tasks continuously.

At a basic level, all filters are designed to separate solid particles from air or fluid and keep them from entering into places where they are not wanted. Think about your morning coffee and what would happen if the coffee filter failed to keep the coffee grounds out of the brewed beverage. You would have very thick and sludgy coffee, not unlike the sludge that can build up in engines with severely contaminated motor oil. In the same way as coffee filters keep grounds out of your java, oil filters capture contaminant particles within the oil to prevent them from causing engine wear. This is important because contaminated oil can reduce engine life from 60 to 80 percent. You probably can see how a poorly designed filter could lead to an engine filled with gunk.

When discussing filters and filter performance at your next barbeque, make sure you talk about the four main criteria: flow, efficiency, capacity and particle size. Proper flow is important so oil can get to critical parts of the engine. If the filter creates an abnormal restriction of oil flow, it can lead to oil starvation and catastrophic engine damage. Efficiency is a measure of a filter’s ability to adequately remove contaminants of a particular size that may critically harm the application. The greater the efficiency, the better that filter is at removing contaminant particles. Capacity describes the amount of contaminants a filter can hold and still flow oil properly. Capacity is described as the service interval or useful life of the filter.

Most of these particles are smaller than what is visible with the human eye. Particles of greatest concern for most applications are 5-25 microns, which is smaller than the diameter of a human hair. Generally, if a filter has large openings, like a window screen, it will have poor efficiency but will flow very well. As screen holes get smaller, more small particles will get caught in the screen. The trade-off is that flow will be restricted. Balancing these two design features is an essential part of filter design.

The type of filter media used in a filter has a big impact on performance. Four major types exist in today’s marketplace, including open-celled foam, cellulose, cellulose/synthetic composite and full synthetic. Synthetic filter media has several advantages over the other filter media materials. Synthetic media has higher capacity and can be modified to a wide range of efficiencies. Synthetic media also removes smaller contaminant particle sizes, and is suitable for extended service intervals because of the increased capacity for contaminants. It is also typically more durable than other filter media, like paper-based materials that use sticky resins to keep fibers from falling apart over time. Cellulose media used in lower-quality filters have larger fibers and bigger holes that let more contaminants pass through the filter. Synthetic filter media is chemically manufactured rather than derived from a tree, like paper, so the fibers are much smaller and specifically designed to capture smaller particles while still keeping good flow of oil through your engine. Ah, the magic of synthetic materials.

AMSOIL incorporates synthetic media into AMSOIL Ea® Filters, which rank among the highest-efficiency filters available. Better filtration equals reduced engine wear. In addition, the extra capacity to hold more contaminants means they keep filtering over extended intervals. When used in conjunction with AMSOIL synthetic motor oil, AMSOIL Ea Oil Filters designated with product code EaO are guaranteed for 25,000 miles/ one year (15,000 miles/one year in severe service). Smaller Ea Oil Filters designated with product code Ea15K are guaranteed for 15,000 miles/one year in normal and severe service. Good oil and good filtration go hand in hand, and AMSOIL Dealers have the products to offer the best of both to their customers.

AMSOIL Signature Series Synthetic Motor Oil Outperforms Competition in New Study

Nine synthetic motor oils were compared to AMSOIL Signature Series 5W-30 Synthetic Motor Oil (ASL). When it was all said and done, Signature Series demonstrated the best overall performance and cost-effectiveness.

Click for larger image

Since AMSOIL introduced the first synthetic motor oil to meet American Petroleum Institute (API) service requirements in 1972, many other synthetic motor oil brands have been introduced. Today, synthetics are widely viewed as superior to conventional motor oils, and demand continues growing, but how do other brands compare to AMSOIL?

A Study of SAE 5W-30 Synthetic Motor Oils

Signature Series 5W-30 Synthetic Motor Oil and nine other synthetic oils were subjected to five industry tests conducted according to American Society of Testing and Materials (ASTM) methodology. The overall annual cost of each oil was also compared. The study included synthetic motor oils exclusively for a number of reasons. First, most motorists now understand that synthetics provide increased performance benefits compared to conventional oils, so convincing consumers of synthetics' superiority is less of an issue. Second, while conventional motor oil sales remain flat, demand for synthetics continues to increase. Third, testing only synthetics facilitates an apples to apples comparison.

Methodology

Testing examined several important areas of motor oil performance, including resistance to deposit formation, wear protection, high-temperature stability, resistance to acid formation and cold temperature performance.

Click for larger image Four-Ball Wear Test results indicate significant differences in relative wear protection between oils. The top four performers limited wear scars to under 0.40 mm. AMSOIL Signature Series Synthetic Motor Oil demonstrated the best wear protection in the Four-Ball Wear Test. Click for larger image  AMSOIL Signature Series Synthetic Motor Oil tested two numbers higher than the nearest competitor.

Each oil was subjected to the following ASTM test methodologies:

• Thermo-Oxidation Engine Oil Simulation Test (TEOST, ASTM D 6335)
• NOACK Volatility Test (ASTM D 5800)
• Four-Ball Wear Test (ASTM D 4172 Mod.)
• Total Base Number (ASTM D 2896)
• Cold Cranking Viscosity (ASTM D 5293)

Test results published in A Study of SAE 5W-30 Synthetic Motor Oils describe and represent properties of oils that were acquired from November 2012 to December 2012. Results do not apply to any subsequent reformulations of such oils or to new oils introduced after completion of testing. All oils were available to consumers at the time of purchase. An independent, third-party lab conducted all tests. Formulations were coded to reduce the potential for bias, and samples were tested in random order. An appropriate number of trials of each oil were run to produce results at the 95 percent confidence level when compared to Signature Series Synthetic Motor Oil. The 95 percent confidence level only applies when comparing AMSOIL Signature Series Synthetic Motor Oil to the other 5W-30 oils. The 95 percent confidence level does not apply when comparing the other oils to one another.

Candidate Oils

The following nine oils were selected for the study:

• Castrol Edge® with Titanium Fluid Strength Technology®
• Lucas Synthetic
• Mobil 1™ Extended Performance
• Pennzoil Ultra™
• Petro-Canada SUPREME Synthetic™
• Quaker State Ultimate Durability™
• Red Line High Performance Motor Oil
• Royal Purple High Performance Motor Oil
• Valvoline SynPower® Full Synthetic Motor Oil

All oils are 5W-30 viscosity and recommended for applications requiring API SN/ILSAC GF-5 specifications.

Results

AMSOIL Signature Series Synthetic Motor Oil displayed the best results in the Four-Ball Wear, Total Base Number and Cold Crank Viscosity Tests. Results in the NOACK and TEOST Tests were also impressive, proving Signature Series Synthetic Motor Oil's excellent high-temperature performance. Other oils performed well in some tests, but not as well in others, illustrating the challenge inherent in formulating a high-quality motor oil that performs well in tests designed to assess optimum engine protection and life. In addition to delivering outstanding performance, Signature Series Synthetic Motor Oil provides maximum cost-effectiveness - even at retail pricing. Because they buy at wholesale, Dealers and Preferred Customers receive even more value. In the end, no other oil demonstrated itself capable of providing the overall performance in these tests and cost effectiveness of Signature Series.

Click for larger image

Although synthetic motor oils are known to provide increased low temperature performance compared to conventional oils, results suggest performance differences between formulations. AMSOIL Signature Series Synthetic Motor Oil demonstrated the lowest cold crank viscosity (3,727 cP).

Click for larger image

 Results demonstrate a range of performance differences. Only Castrol Edge with Titanium Fluid Strength Technology and AMSOIL Signature Series Synthetic Motor Oil limited total deposit weight to 5 mg or less.

AMSOIL 5W-30 Signature Series Synthetic Motor Oil

After 1.6 Million Miles 18 Wheeler Shows No Signs of Quitting

After 1.6 million miles on the original drivetrain and 1.1 million on the factory-rebuilt engine, Jerry Pruett and his AMSOIL-lubed Kenworth show no signs of retiring.

When AMSOIL Dealer Jerry Pruett of Woodhull, Ill. purchased his new 1999 Kenworth over-the-road truck in December 1998, he thought it might run forever if he installed AMSOIL synthetic lubricants. Now with more than 1.6 million miles on the drivetrain and over 1.1 million on the factory-rebuilt engine, "forever" still remains in sight.
The mileage is even more impressive considering how little work the truck has required. The Detroit Diesel Reliabilt^® engine still has virtually all of its original components, including the turbo and fuel injectors. The truck accumulates 2,300-3,000 miles a week hauling loads averaging 27,000-35,000 pounds, with some up to 80,000.
The reliability of the drivetrain is also notable. Though the clutch has been replaced a couple times, the transmission hasn't been touched. "I've done nothing to the transmission. All the gears in it are at 1.6 million miles," said Pruett. The differential gears are also original to the truck.
Pruett runs SAE 60 Super Heavy Weight Synthetic Racing Oil (AHR) in the transmission. He uses Severe Gear^® SAE 190 Synthetic Gear Lube (SRN) in the differentials, although AMSOIL primarily recommends 75W-90 Long Life Synthetic Gear Lube (FGR) in over-the-road applications. "A little bit thicker oil couldn't hurt with the high miles," said Pruett.

AMSOIL Helps Increase Life of Defective Engine

The truck was originally equipped with a Detroit Diesel engine that, unknown to Pruett, contained a manufacturing defect known to cause catastrophic failure early in the engine's service life. Pruett initially installed Shell Rotella during the break-in period. "I wanted the rings to seat prior to switching to AMSOIL," he said. At about 140,000 miles, he installed Series 3000 Synthetic Heavy Duty Diesel Oil (HDD).
With 506,000 miles on the engine, the number three piston failed. "In talking with the mechanics, I found out there was a defect on these engines, and some blew around 300,000 to 375,000 miles," said Pruett. "In one instance, a rod came through the engine and punctured the computer. I felt my engine lasted as long as it did because of AMSOIL." When the mechanics removed the cylinder heads, the original hone marks were still visible on the cylinder walls. "The mechanic said the engine was not wearing out; the oil was doing a great job. Had it not been for the piston failure, it could have run forever."

Detroit Diesel Reliabilt^® Engine

Despite the engine warranty having expired 6,000 miles earlier, Pruett presented his case to Detroit Diesel. "I felt Detroit Diesel was taking advantage of me. Other guys using any old oil were receiving warranty coverage because their engines failed sooner. I told them I was using the best oil in the world and, because of that, the engine lasted longer," said Pruett. "To have that engine last past the warranty was a surprise to them, I think." Detroit Diesel agreed to provide Pruett a factory-overhauled engine at cost, in addition to $4,500 for installation.
The factory-rebuilt engine has since powered the truck for 1.1 million miles, requiring virtually no repairs. "I haven't even pulled the cylinder head off this thing," Pruett said. "I didn't replace the water pump until accumulating over 900,000 miles. Usually a water pump lasts 350,000 miles on a good day." As with the previous engine, Pruett installed Shell Rotella during the break-in period prior to switching to Series 3000 Synthetic Heavy Duty Diesel Oil.
The lone repair required was replacement of the camshaft at about 100,000 miles, barely out of the break-in period when still using Shell Rotella. Pruett believes the camshaft was original to the engine and not replaced when the engine was factory re-built by Detroit Diesel.
With close to 800,000 miles on the engine, Pruett switched to higher-viscosity 15W-40 Synthetic Heavy Duty Diesel and Marine Oil (AME) to guard against excess oil consumption common as engines age.
During a routine 31-point inspection completed when Pruett had a faulty sensor replaced, the mechanic remarked how nice the turbo looked. "They thought it had only been in for a couple months," said Pruett. "It was 12 years old." Pruett credits the Donaldson Endurance™ Heavy-Duty Air Filter for the turbo's longevity. "I was sold on the air filter from day one," he said. "Throttle response was quicker, it boosted the horsepower a little bit and turbo noise decreased."

100,000-mile Oil Changes

Pruett also uses the AMSOIL DUAL GARD^® By-Pass Oil Filtration System fitted with two EaBP110 By-Pass Oil Filters. Regular oil analysis continually indicated the oil was suitable for continued use, allowing Pruett to establish an oil change interval of once per year, or about every 100,000 miles, based on historical data. The EaBP110 By-Pass Oil Filters are changed twice a year, or about every 50,000 miles. Practicing extended drain intervals saves a considerable amount of money each year compared to using conventional oil and standard drain intervals. "Some guys are spending up to $1,200 a year on oil changes when they could be spending half that with AMSOIL," said Pruett. "They're throwing their money away."

Excellent Fuel Economy

Additional savings are realized each time Pruett fills his diesel tanks. "The truck really kind of scares me; it runs so good. I'm still getting about 7 mpg," said Pruett. During a run from Indianapolis, Ind. to St. Louis, Mo., the truck achieved 9.7 mpg. "The truck is capable of that mileage if I can just keep my foot out of it," said Pruett. He has used AMSOIL Diesel Concentrate (ADF) since day one, which not only helps fuel economy but, according to Pruett, has contributed to the fuel injectors lasting as long as they have. He also keeps AMSOIL Cold Flow Improver (ACF) on hand and uses it when conditions dictate.

No End in Sight

Pruett's truck serves as a rolling billboard for AMSOIL. It's covered in AMSOIL decals, along with the contact information for Pruett's AMSOIL Dealership. He shares his AMSOIL story with truckers at every opportunity. Pruett turns 62 in January and has thought about retiring, but, unfortunately for him, his truck has not. "I really want to see how far this truck can go, so I keep on trucking away."

Oil Additives Can Offset the Careful Balance of a Well-Formulated Motor Oil

An overabundance of anti-wear agents, for example, can lead to reduced resistance to corrosion.

Dan Peterson - Vice President Technical Development AMSOIL Inc.

I don't get up on my soapbox very often – partly because I have put on a few extra pounds and don't want to break the box, and partly because it's just not my personality. Not a lot of things really get to me, but when I come across something that does, you don't want to be with me in the car for a long drive. One of these things is engine oil additives. The last time I stopped by the local parts store to pick up a tool for a brake job on my Ford Fusion, I stood in the aisle for a full 10 minutes looking at the huge display of engine oil additives. I was not in a hurry, so I picked up a dozen or so and read the marketing claims.

Wow; it seems almost any internal engine problem in the world can be solved simply by using an engine oil additive. "Restores engine life, eliminates dry starts, eliminates engine noise, restores parts' surfaces AND compensates current wear!" Now I see why people buy all these oil additives. Too busy or just not interested in taking care of your vehicle? Just wait until you have a problem and then buy a solution at the local parts store and you are back in business. Our instant-gratification culture pushes us into believing in quick solutions. In reality, there are very few quick solutions that can correct years of neglect in any area of life, including your internal combustion engine. Very few, if any, engine oil additives solve engine issues overnight or somehow restore engines to their original condition. So how do you get the longest, trouble-free life out of your engine? Use a highquality, trusted brand of synthetic motor oil regularly and don't add any engine oil additives. Formulating a motor oil to perform all the critical jobs required by your engine is a balancing act. You can't just focus on improving one property without testing and evaluating the impact on all critical oil properties. Many times, use of additives improves one property, but causes other properties to take a nosedive. 

Formulating synthetic motor oils is a core strength developed over the past 40 years at AMSOIL, and it is not an easy task. Motor oils need to protect engines against abnormal wear, excessive varnish, sludge, rust and corrosion and damaging foam. Motor oils also need to remove heat, help meet fuel economy standards, keep engine seals from leaking and keep catalytic converters working effectively over their projected lives.

Many negative outcomes derived from using engine oil additives have been documented over the years, including accelerated corrosion, excess oil thickening in cold temperatures and increased deposit formation. Most of these negative outcomes are relatively complicated chemical interactions, but just like your family is interconnected, so is the chemistry in your motor oil. When you add Uncle Buck to your family for a week, you and the kids all have a lot more fun staying up late and listening to stories, but he upsets the family balance. The kids have black circles under their eyes from staying up too late, you argue with your spouse about a few choice new words the kids picked up and you have to clean up cigar butts all over the garage when he finally leaves. Seems fun at first, but a week-long visit proves having Uncle Buck live with you for good isn't such a good idea.

The chemicals in motor oils are all interconnected and work together like a family unit to provide all the important properties required to keep your engine operating well. Most motor oils are designed with a measured amount of wear protection and deposit control. The problem comes when you add a whole bunch of extra or new wear protection or deposit control, and it ends up creating corrosion or destroying coldtemperature properties. Motor oils that perform well have some Uncle Buck built in, but at an appropriate level that does not upset critical chemistry in other areas designed to keep your engine running smoothly over the long run.

If you want a more detailed explanation by industry experts, a recent Noria announcement outlined that "Aftermarket oil additives can backfire." In the book, "Practical Handbook of Machinery Lubrication," the following description is listed:

"Increasing the percentage of a certain additive may improve one property of an oil while at the same time degrade another. When the specified concentrations of additives become unbalanced, overall oil quality can be affected. Some additives compete with each other for the same space on a metal surface. If a high concentration of an anti-wear agent is added to the oil, the corrosion inhibitor may become less effective. The result may be an increase in corrosion-related problems."

It's a much fancier way of saying too much of your Uncle Buck is not good for your marriage. Next time you talk to someone who is contemplating using one of those flashy new engine oil additives, tell them about the importance of maintaining the critical balance in motor oil and what can happen when it becomes unbalanced. 

AMSOIL Synthetic Motor Oils