Motor Oil Information
WHAT MOTOR OIL DOES
Engine oils are complex mixtures of base oils and additive components designed to perform a variety of tasks: separating and lubricating moving parts, reducing engine wear, helping prevent deposits from forming on internal engine components, removing and suspending dirt and contaminants in the oil until these contaminants can be removed at the next oil change, cooling engine parts, enhancing engine fuel economy, providing protection over a wide temperature range and even helping to protect the emissions system. In other words, they do a lot more than just lubricate.
The right motor oil also helps protect your emissions systems. Catalytic converters can deteriorate over time and are expensive to replace. A high-quality motor oil helps protect the emissions system by minimizing its own impact on these devices. To assure base quality, always look for the American Petroleum Institute (API) Starburst and Donut.
WHY IS A MOTOR OIL’S ABILITY TO CLEAN IMPORTANT?
Dirt is created inside your engine as part of the normal combustion process, so keeping engine components clean is essential. If your engine components and oil passages are dirty, your vehicle performance and efficiency suffer. Deposits also trap heat inside your engine like an insulating blanket. ATROD® motor oil doesn’t just help prevent sludge, it can clean up sludge in the first oil change.
HOW DOES ATROD® MOTOR OIL PROTECT MY ENGINE?
By cleaning your engine:
ATROD® motor oils don’t just help prevent sludge, they’re designed to clear away sludge, dirt, debris and deposits from engine components and prevent blockages of important oil pathways. The oil locks up the dirt, rendering it harmless until it is removed at the next oil change.
By reducing friction and minimizing wear:
ATROD ® motor oils form a protective film over your engine components and have special additives between moving surfaces, preventing contact and reducing drag. This helps your engine to operate as quietly and effectively as the day it left the factory.
By removing heat:
ATROD ® motor oils carry heat from hot areas, such as around the piston rings where temperatures can top 300oC, helping to protect critical parts from intense heat.
By preventing corrosion and rust:
ATROD ® motor oils protect your hardworking engine components from oxidation, and the resulting corrosion, over the normal oil-change interval. Our field test data shows that ATROD ® motor oil stands up to extreme conditions and protects your engine from searing desert heat and harsh cold winter driving conditions.
ENGINE OIL FORMULATION
Engine oil is comprised of two basic components—base oils and additives. The base oils constitute 70 to 85 percent of the total, while additives round out the remaining 15 to 25 percent.
These additives, known collectively as the Performance Additive Package, are comprised of dispersants, detergents, anti-wear additives, friction modifiers, antioxidants, anti-foam additives and corrosion inhibitors. In addition to the Performance Additive Package, motor oil additives also include a viscosity index improver and a pour-point depressant.
A dispersant helps keep sludge from forming on internal engine parts by suspending contaminants in the oil until they can be safely removed at the next oil change.
Detergents operate on high-temperature surfaces, such as the piston-ring area and the piston under-crown, helping to prevent deposits. These detergents get consumed over the life of your oil change.
Anti-wear agents form a protective coating on metal surfaces. They also provide an antioxidant boost. Anti-wear agents operate under high temperatures and high load conditions, particularly protecting cams, lifters, piston rings and cylinder walls. Anti-wear agents cloak these surfaces in a “sacrificial layer” or film, which is consumed in the protective process. Without this “sacrificial layer,” metal-to-metal contact would occur. Like detergents, anti-wear agents also get consumed over the life of your oil change; another reason you should always change your oil at recommended intervals.
These do what you think; they reduce friction under high loads and high temperatures, helping to maintain peak efficiency and fuel economy. The effectiveness of these additives diminishes over time as the oil ages.
Oxidation results from exposure of the oil to oxygen at high temperatures. It’s not a good thing. The results of such exposure can accelerate the aging of the oil contributing to oil thickening, sludge and deposits. Antioxidants help slow oxidation in the oil to help keep engines running clean.
Foam-causing air bubbles create a variety of problems in oil. They make oil harder to pump to vital engine parts, reduce the oil’s lubrication effectiveness, and inhibit the oil’s ability to help keep the engine cool. A foamed-up oil can result in serious engine damage. An anti-foam additive helps prevent these problems, specifically at high temperatures.
Rust and Corrosion Inhibitors
It might sound strange, but internal engine parts can be subject to rust and corrosion. Rust and corrosion inhibitors coat metal surfaces, protecting against these hazards.
Viscosity Index Improvers
The Viscosity index measures an oil’s ability to resist changes in viscosity as temperature changes. Viscosity index improvers utilize polymer additives to help maintain oil viscosity over a wide range of temperatures. The use of Viscosity index improvers allows the formulation of multi-grade engine oils, such as SAE 20W/50 and 10W/40.
These are used in multi-grade oils to provide good oil flow at low temperatures. Flow is important in cold engines as oils that are difficult to pump through the engine require additional energy to circulate—like a clogged artery. This results in added stress on the engine and decreased efficiency.
TYPES OF MOTOR OIL
Motor oil can be segmented into four basic varieties—synthetic oil, synthetic blends, high mileage oil and conventional oil.
Synthetic motor oil is a laboratory synthesis of precisely controlled ingredients created by oil engineers, scientists and chemists. When combined with a high-performance additive package, this results in an oil with the highest levels of lubrication and engine protection, generally offering better protection at startup, better cleansing qualities, enhanced durability and better protection against heat buildup.
Synthetic blend motor oils use a mixture of synthetic and conventional base oils for added resistance to oxidation (compared to conventional oil) and to provide excellent low-temperature properties and are recommended for cars, trucks, vans and SUVs that regularly carry heavy loads, tow trailers and/or operate frequently at high RPMs.
High-mileage motor oil is specially blended for older vehicles, or vehicles with higher mileage. Typically, 120,000 kilometers is the figure used regarding high mileage oil. Some high mileage, high-performance cars, however, will be better served by continuing to use a synthetic motor oil. That said, a special high mileage motor oil blend, with its unique additives and viscosity, helps reduce oil burn-off, helps in sealing oil leaks and helps improve combustion chamber sealing to help restore engine compression. It all adds up to enhanced performance in older engines.
Conventional motor oil is what its name implies—it uses base oils enhanced in the blending process with chemical additives to help meet the manufacturer's desired levels of heat tolerance, breakdown resistance and viscosity (viscosity simply being a technical term for the thickness and fluidity of the oil). Conventional motor oil can be had in a range of viscosity grades and quality levels, from adequate to an extensively designed, high-quality lubricant. Conventional motor oil is recommended for drivers with low-mileage, late-model cars whose driving habits can be described as routine—commuting, running errands, vacation driving at relaxed cruising speeds.
OIL GRADE DESIGNATIONS
Motor oils use a rating system developed by SAE, which is the Society of Automotive Engineers, to classify oil by viscosity. We’re all used to seeing designations like SAE 10W/40 or SAE 20W/50, so let’s see what they really mean.
For multi-grade viscosity oils, the cold-temperature viscosity is labeled with a “W,” which stands for “winter.” Thus, in an SAE 10W-30 oil, the “10” is the cold-temperature viscosity rating, and the “30” is the high-temperature viscosity rating. This combination provides an oil that flows well at low temperatures, but still protects the engine at high temperatures.
For comparison’s sake, SAE 5W-30 and SAE 0W-30 will flow better at even lower temperatures than 10W-30 while still providing protection at high temperatures. Just remember, the “W” stands for winter.
Please refer to your owner’s manual or our Oil Selector tool to ensure you are using the recommended motor oil for your vehicle.
The API “donut”
A known identifier on motor oil containers is the API “donut” typically found on the back label. It’s divided into three parts. The top half of the circle (2) indicates the API service rating, also called the performance level. The center of the circle (3) denotes the SAE viscosity, which we just discussed. The lower half of the circle (4) indicates whether the oil has demonstrated certain resource conserving or energy-conserving properties.
In the top part of the donut the words “API Service XXXXX” (5) indicate the type of engine and performance the oil provides. API Service SN the current rating means “S” for Service Station oil (for gasoline engines) and N the current level of service. Or it will say “API Service CJ-4.” API service CJ-4 means “C” for commercial engines (diesel engines) and J-4 where J is the current performance level and 4 indicates a 4-stroke diesel (a 2 will be used for 2-stroke diesel engines).
Check your owner’s manual for the recommendation for your vehicle. Older vehicles can use the current designation. All designations are compatible with those that preceded them with the exception of a few antique vehicles. Only the current API categories are indicated within the donut.
FREQUENTLY ASKED QUESTIONS
Is it necessary to use a stabilizer or additive with every oil change?
Nope. Today’s engine oils are formulated to fully protect the engine. They don’t need extra help.
When should I change my oil?
You should change your oil and filter at, or before, the end of the oil-change intervals provided by your vehicle’s manufacturer. These intervals are based on mileage or time. By doing this, you can help keep your engine oil in good condition and provide the best protection for all your components.
How should I dispose of my old oil after an oil change?
Used oil can pollute the environment and should never be poured down the drain. The ATROD® Clean Change campaign helps customers protect the environment. You can drop off old oil and oil filters at your closest Jiffy Lube®, Walmart Tire & Lube Express or most oil change centers among the USA to be recycled properly.
THINKING OF TRADING UP TO A SYNTHETIC?
Why Is It Important to Use a Synthetic Oil That Cleans?
Simply put, a cleaner engine is better protected and more responsive. It’s a fact of life that all engines generate contaminants. Contaminants such as soot, carbon, and sulfuric and nitric acid are inevitable byproducts of the combustion process. And all of them end up in your motor oil to varying degrees. So the question isn’t whether you need an oil that cleans, but how well your oil cleans the dirt and deposits your engine generates.
Why Trade Up to a Full Synthetic Oil?
Part of the job of an engine oil is to suspend the contaminants within the oil until your next oil change. It’s a fairly daunting task for engine oil to suspend all the contaminants thrown at it; the truth is that full synthetic motor oils like ATROMAN® do a better job of preventing deposits on engine surfaces than conventional oils and synthetic blends can do. In fact, both motor oils exceed certain cleanliness standards that conventional oils and synthetic blends just can’t meet.
SYNTHETIC OIL MYTHS
Myth: Once you switch to synthetic oil you can never switch back. This is one of the most persistent myths about synthetic oil—and completely untrue. You can switch back and forth at any time. In fact, synthetic blends are simply a mixture of synthetic and conventional oils. It is advisable that you use the same oil for top-ups if needed, thereby giving you the best protection from the oil that you have chosen.
Myth: You shouldn’t use synthetic oil in an older vehicle. The myth is rooted in the idea that synthetic oil is “slipperier,” lower in viscosity, or not as compatible with seals and will therefore leak or leak more in places conventional oil might not. Again, completely untrue. Synthetic oils will enhance the engine protection in older vehicles just as they do for new engines.
Myth: You should break in your engine with conventional oil before you start using synthetic oil. Again, there’s no manufacturer we’re aware of that makes this recommendation. Mercedes, Porsche, Corvette, some Cadillacs, Volkswagen, Hyundai and many other manufacturers’ cars come from the factory with synthetic oil.
Myth: Using a synthetic oil voids a car’s warranty. Untrue.
Myth: Synthetics made from Group III base oils are not true synthetics and are not as good as PAO-based synthetics in Group IV. Again, untrue. Synthetics made from Group III oil can, in some cases, outperform those made in Group IV oils in some areas of performance.
ATROMAN KEEPS PISTONS UP TO 25% CLEANER THAN CONVENTIONAL OIL
In a recent head-to-head test*, no leading synthetic motor oil kept pistons as clean as ATROMAN™. In fact, full synthetic ATROMAN™ motor oil beat conventional oils hands down. So if you are thinking about trading up to a full synthetic motor oil, choose the one that keeps pistons cleaner than any other leading synthetic oil.
(*Based on ASTM Sequence IIIG piston deposit test using SAE 5W-30. Pistons from standard V6 engine in Sequence IIIG test. )
NOTHING KEEPS YOUR ENGINE CLOSER TO FACTORY CLEAN.
The Goal: Design an oil that far exceeds the toughest standards for engine cleanliness—engineered to keep a car’s engine in pristine condition, as it was the day it left the factory
It took one of those stake-in-the-ground moments for us to realize, with engine tolerances becoming so uncompromising and the role of the motor oil so important, we should create a new kind of motor oil that keeps engines as close as possible to factory clean. And then we went about achieving it. The end result of that exploration is new ATROMAN™.
Tested Clean Synthetic Oil
Both of these front engine covers were subjected to the same industry test designed to simulate moderate temperature taxicab service, or the typical driving cycles of an urban and suburban delivery service. The test evaluates the oil’s ability to prevent sludge and varnish formation.
The engine cover on the left reflects a passing grade. The engine cover on the right shows the same test conducted with ATROMAN™.
Amazing, isn’t it?
ATROMAN™ full synthetic oil prevents sludge and damaging deposits from forming by seeking out, dissolving and neutralizing contaminants safely into the oil and cleans up sludge by gently lifting deposits off engine surfaces and dissolving them into the oil.