You guessed it, the key ingredient to engine oxidation is oxygen.
Oxygen comprises about 20 percent of our atmosphere. It’s the third most common element in the universe. Without it we’d all be doomed.
And yet too much of it can cause problems inside your engine.
What is oxidation?
Oxidation occurs when the addition of oxygen changes a chemical substance. Take an apple, for example. Everyone knows that oxygen will quickly cause a cut apple to turn brown. Or metal. Oxygen can cause rust to form on some metals in a matter of days. Have you ever noticed your brakes grinding after having left your car sit for a couple days in wet weather? That sound is your brake pads scouring rust from the rotors. Never worry about that one as driving soon burns that off..
More wear on or in your engine occurs during storage. The oxidation discussed below can be detrimental. And that is not limited to the motor oil but the coolant system as well.
Motor oil isn’t immune to oxidation. As oil reacts with oxygen, a permanent chemical change occurs that causes oil molecules to lose one or more electrons. This can result in several problems, including…
Formation of sludge and deposits that reduce engine efficiency and increase the risk of engine failure
Increased oil viscosity, which reduces fuel efficiency
Additive depletion, reducing the oil’s effectiveness
Accelerated degradation, causing you to change oil more often
Heat accelerates oxidation
Every 18ºF (10ºC) increase in temperature doubles the rate of oxidation. That doesn’t bode well for motorists driving modern turbocharged vehicles that create increased heat compared to older vehicles. Or that Harley waiting in lines of traffic at events when block temps exceed 400F.
Heat isn’t the only oxidation accelerant – certain metals, acids and water can also hasten oxidation. So can large volumes of entrained air, known as foaming.
Can we prevent motor oil oxidation?
Unfortunately, no. Nature is a relentless force, and all motor oil will eventually oxidize to some degree. But we can dramatically slow oxidation through use of synthetic base oils and quality oxidation-inhibitor additives.
AMSOIL synthetic lubricants are formulated using base oils with a saturated molecular structure, meaning oxygen is prevented from attaching. This provides inherent heat and oxidation stability compared to unsaturated conventional oils.
And, because AMSOIL synthetic lubricants don’t contain contaminants like conventional oils, their base composition doesn’t accelerate oxidation.
AMSOIL synthetic lubricants also contain high-quality oxidation inhibitors. These additives are sacrificial in nature, meaning they’re designed to deplete over time. Because AMSOIL synthetic lubricants have inherently better oxidation resistance, their oxidation inhibitors last longer since they don’t deplete as rapidly.
When components and additives are selected for blending, cost is never a deciding factor thus our formulations will always result in the best of class. As AMSOIL does not have stock holders there are no outsiders to effect our decisions to always use the very best.
So, what does that mean to me?
That all adds up to a motor oil that…
Lasts longer despite intense heat and stress
Helps keep your engine cleaner and more efficient
Saves money in the long run through reduced maintenance
And as a bonus you enjoy added performance
So, while oxygen lets you breathe, AMSOIL synthetic motor oil lets you breath easy since your engine is protected against oxidation.
For all the grin-inducing benefits of owning a European car – finely tuned performance, sophisticated styling, prestige – they can be a pain. According to this list, four of the top five most expensive vehicles to maintain hail from across the pond. Notice Volkswagen is among the lowest maintenance costs. The exception to the rule.
Not only that, but they require specialized oil that differs in many ways from the good ‘ol American motor oil you use in your Ford or Chevy. Here are four reasons why.
#1 Everyone likes clean air
The European Union maintains more strict standards for the carbon dioxide hoax (CO2) and carbon monoxide (CO) emissions than we do. (Our standards for nitrogen oxides [NOx] and particulate matter [PM] are more strict, however.) Because modern diesels emit lower CO2 than gasoline engines, the European market pivoted toward increased use of diesel-powered vehicles in the 1990s. Diesels also provide the advantage of better fuel economy.
One drawback, however, is the higher levels of NOx and PM diesels produce. To counteract this, diesel-powered European vehicles are equipped with diesel particulate filters (DPF) and catalysts designed to reduce pollutants from the exhaust before it exits the tailpipe.
Here’s where motor oil comes into play.
An oil’s formulation can have a negative effect on sensitive emissions-control devices. Certain components in the motor oil formulation, such as sulfated ash, phosphorus and sulfur (known collectively by the pleasant term SAPS), can reduce the effectiveness and life of DPFs and other emissions devices.
For that reason, motor oils formulated for European vehicles often contain lower SAPS levels to protect emissions-control systems.
#2 Longer oil change intervals
Europeans have long since accepted what’s only recently caught on in North America – longer oil change intervals. Many motorists in the states are just a few years removed from blindly practicing 3,000-mile oil changes. Except, of course, AMSOIL customers who have been practicing extended drain intervals since 1972. But that’s a digression for another day.
Europeans are accustomed to changing oil far less often, with drain intervals of 16,000 km (10,000 miles) or so quite common. One reason is the higher cost of oil in Europe. Another is the differences between manufacturer recommendations. For example, oil changes for 1999-2013 BMWs are required only every 15,000 miles. In the U.S., most people change oil around every 5,000 miles. The figure increases by a few hundred miles if their vehicle is equipped with an electronic oil-life monitoring system.
Longer drain intervals common with European cars require an oil capable of protecting against wear, deposits and sludge for the duration, which requires a more robust oil.
#3 The thick and thin of it
Check the owner’s manual of most European vehicles for which viscosity of oil to use, and you’ll likely find a chart that suggests different viscosities for different operating temperature ranges. In cold weather, the OEM may recommend 5W-30. In warm weather, 5W-40. Traditionally, drivers settle on an 0W-40 or 5W-40 to offer the best of both worlds – good cold-flow at startup to protect against wear and good resistance to heat once operating temperatures are reached.
#4 Automaker approvals
Staying in your owner’s manual, the OEM also recommends you use an oil that meets a specific performance standard. In the U.S., it’s typically an industry-wide motor oil specification, such as API SN PLUS.
European OEMs are different, however. They typically maintain their own motor oil performance specifications. Drivers of VWs, for example, need to use an oil that meets the requirements of VW’s own performance specs. The same holds for Mercedes, BMW, Porsche and other European cars.
Complicating matters, each OEM motor oil specification is slightly different. One OEM may require oils that offer better performance against oxidation, while another requires better resistance to viscosity loss.
OEM specifications tend to be more strict and require increased motor oil performance than industry specs. This, of course, requires more advanced (and typically expensive) motor oil technology delivered almost exclusively by synthetics.
General Motors, for its part, has taken a page out of the playbook of its European car counterparts by maintaining its own GM dexos performance specification.
These differences mean you’d better make sure you’re using the correct oil in your European car. Fortunately, we make it easy for you by formulating a full line of synthetic motor oil for European cars. If you don’t know which your car requires, check out our handy Product Guide.
To flush or not to flush. (One of our best sellers here in Sioux Falls)
It’s a question whose answer is obvious in the bathroom, but vigorously debated in the garage.
Let’s get right to the point. Is an engine flush good or bad?
Spend a few minutes perusing online forums and you’ll find a range of answers to this question, often involving a 1980s Trans-Am, Camaro or other car that someone thrashed on for years, parked in a pasture for a decade and now wants to revive with an engine flush.
Here’s what we’ll cover:
What is an engine flush?
How deposits and sludge form
Can engine sludge be removed?
Is an engine flush necessary?
Engine flush as part of maintenance
5 benefits of an engine flush
Engine flush products
Watch: How to do an engine flush (video)
What is an engine flush?
An engine flush is an aftermarket chemical additive designed to clean accumulated deposits, sludge and other gunk from your engine. You pour it into your engine’s oil-filler port and idle the engine for about 10-15 minutes. It mixes with the oil and circulates through the engine, helping dissolve sludge and clean deposits. Then, you drain the oil (along with much of the gunk, in theory), change the oil filter, add fresh oil and return to the business of driving.
How deposits and sludge form inside an engine
If it did its job, your engine’s performance will return to the heady days of its youth, when it delivered maximum power and efficiency. Over time, however, harmful deposits and sludge may have accumulated, causing power and performance loss.
The tiny openings in the oil pickup tube screen can easily plug with sludge, starving the engine of oil.
Deposits and sludge can form for several reasons, including…
Frequent short trips that don’t allow the oil to fully warm up and evaporate moisture
Ingestion of air-borne dirt
Fuel dilution
High heat breaking down the oil
As it settles, sludge can clog narrow oil passages or the screen on the oil pickup tube, restricting oil flow to vital parts, especially the upper valve train. Deposits can cause the rings to stick, reducing engine compression and horsepower.
Can engine sludge be removed?
Yes. The proper detergents in the correct concentration can dissolve engine sludge, deposits and varnish. Ideally, sludge won’t form at all; however, sometimes mechanical issues arise, such as a leaking head gasket, and the formation of sludge occurs. If sludge does form, the oil’s detergents help dissolve and disperse sludge to clean the engine.
This is more challenging than it sounds. For starters, the oil must perform several functions, not just help prevent engine sludge. For that reason, oils contain a limited concentration of detergents (compared to an engine flush product) to ensure room in the formulation for other additives that protect against wear, fight oxidation, combat rust and more.
An engine flush product, on the other hand, is designed solely to clean. AMSOIL Engine and Transmission Flush, for example, contains nothing but potent detergents, making it a more effective cleaner than motor oil. Plus, it cleans at the molecular level, ensuring deposits are dissolved and properly exit the engine with the oil when it’s drained. This is important since some motorists fear that an engine flush will free large chunks and cause an avalanche of debris to clog passages inside the engine. AMSOIL Engine and Transmission Flush guards against this scenario.
Is an engine flush necessary?
A good engine flush can help loosen deposits and dissolve sludge, returning your engine to like-new condition. However, in old engines with high miles, sludge may be the only barrier keeping oil from seeping through worn or cracked seals. Removing the sludge exposes the seals for what they really are – junk. Soon, your engine begins leaking oil, and you’re mind instantly associates the engine flush product with an oil leak.
In reality, the seals were already bad; the flush simply revealed their true condition.
If you suspect your vehicle falls into this camp, leave well enough alone and skip the engine flush. It’s probably not worth trying to revive an engine in such poor condition without first fixing the bad seals or other defects.
In effect, you’re choosing your problem: either sludge and deposits robbing performance or, if you clean the engine, the seals showing their true condition.
An engine flush is part of a good maintenance regimen
But that’s not to say an engine flush is never a good idea. In fact, it’s often the first step in helping restore a neglected vehicle to top-notch performance. And, often when you buy a used vehicle, that’s what you’re getting – a vehicle whose owner found antiquing on Saturday afternoon more enjoyable than changing oil or dropping the transmission pan. Consequently, your “pre-owned” ride, while not complete junk, may boast a sketchy maintenance record.
In these cases, a potent, detergent-based flush can help prepare the engine for new oil, loosening sticky valves or rings and helping remove harmful sludge. While not a required step when switching to AMSOIL synthetic motor oil, we do recommend flushing your engine if you want to give your vehicle a fresh start.
5 benefits of an engine flush
1. Prepares your engine for new oil
An engine flush helps loosen sticky valves or rings and remove harmful sludge and other contaminants. By cleaning the engine prior to installing fresh oil, you ensure the new oil functions as intended and delivers maximum protection. The oil won’t last as long or protect as well if it must contend with sludge and deposits from the previous oil.
By the way, we don’t require use of AMSOIL Engine and Transmission Flush before switching to AMSOIL synthetic motor oil, but we recommend flushing your engine if you want to give it a fresh start.
2. Helps increase fuel efficiency
Contaminants circulating throughout the engine can lead to oil breakdown and increased viscosity – and higher-viscosity oil requires more energy to circulate throughout the engine. Sludge and deposits on engine parts can also increase resistance, which wastes fuel to overcome. Cleaning the engine helps ensure parts move efficiently, maximizing fuel economy.
3. Helps reduce emissions
If deposits in the piston-ring lands cause the rings to stick, oil can migrate into the combustion chamber, where it burns. This not only leads to harmful deposits, it also increases exhaust emissions as the burned oil exits the tailpipe. A good engine flush helps free stuck rings and reduce oil consumption, in turn reducing emissions.
4. Helps reduce heat
Excessive heat is bad for your engine and the oil. Extreme heat reduces engine efficiency while increasing the rate at which the oil oxidizes (chemically breaks down). Sludge and deposits act as insulators that prevent the engine from dissipating heat as designed. Flushing your engine helps ensure it manages heat properly for optimum efficiency and oil life.
5. Convenience
This might not apply to every engine flush, but it applies to AMSOIL Engine and Transmission Flush. It delivers results after just one application. And it only takes 10-15 minutes to use. Plus, you can safely use it in gas or diesel engines and automatic transmissions. While some solvent-based flush products require a cumbersome disposal process, AMSOIL Engine and Transmission Flush uses a detergent-based formulation. As such, you can dispose of it easily with waste oil.
Cylinder head pre-cleanup. Note the sludge around the valve springs and push rod openings.
Post-cleanup with AMSOIL Engine and Transmission Flush, the cylinder head is noticeably cleaner.
Engine Flush Products: I use AMSOIL Engine and Transmission Flush
For the record, I’ve used AMSOIL Engine and Transmission Flush on three different pre-owned vehicles in my time, and it’s worked great. One of them, a 1999 Honda CR-V, accumulated more than 220,000 miles before rust forced me to replace it. Another, an Oldsmobile Intrigue, ran great until a computer problem forced me to trade it off…for the CR-V. The third ran great, but I sold it off after it, too, rusted out.
In sum, flush your engine if you want to give your vehicle a new lease on life. AMSOIL Engine and Transmission Flush, as the name indicates, also works great for cleaning automatic transmissions. Check out this post to determine if a transmission flush or pan drop is better for you. But if you have any reservations about disturbing sludge or deposits that may be holding your old, high-mileage engine together, consider skipping it. It’s up to you.
How to do an engine flush
If you are looking for the best way to flush your engine this weekend, here’s a quick video that will walk you through the process, courtesy of MyJeepStory.
It’s a disgusting phenomenon. Even the word sounds gross, like the thing it’s describing. The word for this is onomatopoeia, a strange word that many of us learned in high school English class. Splash. Grunt. Whoosh. Swish. Hiss. Frumpy. You know what I’m talking about.
What is sludge?
Sludge is a black gelatinous goo that renders equipment inoperable if not dealt with. And long before the engine’s demise, sludge can foul its sensors and interfere with performance. Some mechanics call it the “black death.”
How does motor oil, which is fluid, become a semi-solid paste or gel inside an engine?
How engine sludge forms
Essentially the formation of engine sludge is the result of a series of chemical reactions. The lubricant itself degrades as it is exposed to oxygen and elevated temperatures. The higher the temperature, the more rapid the rate of degradation. The by-products of this reaction form highly reactive compounds that further degrade the lubricant. Their by-products then react with other contaminants, forming organic acids and high-molecular-weight polymeric products. These products further react, forming the insoluble product known more commonly as sludge. What begins as a thin film of lacquer or varnish deposits on hot or cold metal surfaces eventually bakes into an expensive mess.
Synthetic base oils help prevent sludge
Fortunately, sludge and varnish deposits are something we oil manufacturers have a measure of control over. Using thermally stable base oils reduces the rate of initial degradation (oxidation). A good example of this is the use of common synthetic base oils such as API Group III, PAOs and Esters. Anti-oxidant additives help reduce the rate of degradation as well. One of the most widely used is zinc dithiophosphate. Not only is it an excellent oxidation inhibitor, it is an outstanding anti-wear additive as well.
So do high-quality additives
We can further address many of the issues occurring after the initial oxidation stage. Additive chemistry such as detergents and dispersants are commonly part of motor oil formulation. They help promote the suspension of contaminants within the oil and keep them from agglomerating. Detergents, which are also alkaline in nature, assist in neutralizing acids that are generated in the sludge-building process. Anti-oxidant, dispersant and detergent additives are consumed during use. To achieve maximum life expectancy, use an oil with high concentrations of these additives.
Severe service invites sludge
Good lubricants minimize sludge and varnish issues. How the equipment is used also has a bearing on the likelihood of sludge or varnish issues.
Stop-and-go driving, frequent/long-term idling and operation in excessively hot or cold weather can all increase the likelihood of sludge and varnish, especially if using more volatile conventional oils.
Interestingly, most auto manufactures note in their owner’s manual that operation under any of the above conditions is considered severe service and requires more frequent oil changes. From a mechanical standpoint, things like adding too much oil to the oil sump, antifreeze contamination, excessive soot loading, excessive oil foaming, poor engine combustion efficiency, excessive blow-by and emission-control-system issues can all lead to the formation of sludge and varnish.
By practicing good maintenance and using properly formulated, premium synthetic lubricants, like AMSOIL synthetic motor oil, your vehicle won’t succumb to the “black death.”
All ADVANCED AMSOIL products are available NOW in Sioux Falls at your full time AMSOIL store: The Synthetic Warehouse at 4610 W. 12th St. Sioux Falls, SD 57107
