Today’s article we would like to post about sludge and how it can be detrimental to the life of your engine. What can you do about sludge that forms inside your engine and lastly how can you prevent sludge from forming?
Each month, AMSOIL Inc sends out a magazine to all registered dealers and preferred customers. The AMSOIL Magazine if full of information about products, technical articles and business building tips. The article below was taken from the August 2015 dealer magazine.
Read the article, written by Dan Peterson Vice President, Technical Development at AMSOIL Inc.

Synthetic lubricants resist sludge better than conventional oils.

Sludge is the result of insoluble debris overloading the lubricant.

Anyone who has purchased a new vehicle knows its value depreciates the instant it’s driven off the lot. In some ways, lubricants behave the same way. Once you install an oil or transmission fluid, it begins to age, especially conventional lubricants.
Oxygen reacts with the lubricant and results in a permanent chemical change where oil picks up oxygen and gets thicker. Just like oxygen attacks metal surfaces and causes corrosion, it negatively affects lubricants and reduces their ability to lubricate, cool and protect components. Excessive heat speeds the oxidation process. In fact, every 18 ̊F (10°C) increase in temperature doubles the rate of oxidation.
Adding to the challenge, contaminants begin to form during normal operation. In engines, hot combustion gases can blow by the piston rings and contaminate engine oil. Glycol from engine coolant, water that forms with temperature fluctuations, soot (in diesels) and fuel are other common contaminants that affect lubricants. Left unchecked, contaminants accelerate chemical reactions, which overloads the lubricant and causes the formation of sludge – a gelatinous substance that wreaks havoc in engines.
Sludge can block the oil passages and oil-pump pick-up screen, resulting in oil starvation. You don’t have to be an engineer to know what eventually happens to an engine that runs without oil. Often, the negative effects are cumulative rather than sudden. Many engines with variable valve timing (VVT) use oil-pressure-operated mechanical devices to change valve timing, duration and lift. Sludge can plug the solenoid screen or oil gallies and impact the operation of VVT
mechanisms, eventually leading to a costly repair bill. Sludge reduces efficiency and increases time and money spent on maintenance.
Although we typically associate sludge with engines, it also affects transmissions, particularly those used in severe-service applications. Modern automatic transmissions feature a dizzying array of oil passages, gears, clutch packs and electronics. A steady supply of clean, high-quality transmission fluid is vital to getting the most out of your transmission. Sludge can clog the narrow oil passages and cause delayed or elongated shifts. Just as in engines, severe cases of sludge in transmissions can plug filters, leading to starvation and catastrophic failure.
Given the laws of chemistry, it seems nearly impossible to protect your vehicles against sludge, especially since modern engines and transmissions run hotter than their predecessors. But the good news is high-quality synthetic lubricants resist the tendency to form sludge while extending oil service. As you may suspect, synthetic base oils do a better job resisting sludge than conventional base oils because they are naturally more resistant to oxidation. AMSOIL synthetic lubricants are formulated with base oils that resist reactions with free radicals that create sludge, similar to how you need to keep up a strong immune system to resist chemical and genetic changes that can lead to cancer.
Detergent, dispersant and antioxidant additives also play a key role. They help maintain internal cleanliness by suspending contaminants, minimizing contaminant agglomeration and fighting free radicals to keep this cancer from forming in your engine.
Dirty components run poorly, pollute and don’t last. They cause system failures in engines, compressors and gearbox systems that dramatically increase downtime, increase operating costs and reduce equipment life. Clean lubrication systems, on the other hand, require less maintenance, produce more energy, use fuel more efficiently, increase equipment service life and run cleaner.
AMSOIL synthetic lubricants not only resist oxidation and sludge formation, they can help clean existing deposits in neglected engines due to superior detergency. With modern engines and equipment demanding higher-quality lubricants, it’s good to know AMSOIL synthetic lubricants are formulated to protect against sludge in the toughest operating conditions. Just like we all want to stay healthy so we can live long and purposeful lives, we want to keep sludge from forming in our engines so they can do the same.

How does one know if they have sludge forming inside their engine?


Engine Sludge Photo

One of the first things you can do is take a look at your dipstick. Is it clean or does it have build up on it? Next thing if you can take off the oil filler cap. Using a flashlight look inside the oil fill hole and see if you can spot and sludge build up. Another measure to determine sludge is to look at the oil when you drain it, does it come out in clumps or seem to be really thick? You can also pull your value cover or take off  your oil pan to determine the extent of sludge build up in your engine.

If you determine you have minor sludge build up, we recommend the following treatment:

  1. Use the AMSOIL engine flush¹ product according to directions.AMSOIL Engine and Transmission Flush
  2. Change oil and filter² with a quality conventional oil. Drive 500 miles and check and see if there is still sludge in  your engine. If it seems to be free of sludge then change oil and filters using AMSOIL synthetic OE or XL synthetic motor oil. You can also do another flush at this time as a precaution. Drive 3,000-5000 miles. During this time the high detergent in AMSOIL synthetic motor oils will continue to clean your engine. If there is still a significant amount of sludge, repeat #2 again with an engine flush and 500 mile oil change. Repeat until desired results are achieved then move to #3.
  3. At no longer than 5,000 miles, change oil and filters. At this time, determine if you can safely extend oil changes to 10,000 using AMSOIL XL synthetic motor oil. (Your engine should look clean, the oil should be still clean at the 5,000 mark)
    During this oil change interval as well as during previous oil changes, monitor your engine oil levels to determine if there is higher than normal consumption. Sometimes during the cleaning phase you can have higher consumption.
  4. After the 10,000 mile oil change now you can decide if you would like to move up to the Signature Series Oil. This is the premier line of AMSOIL engine oils which are capable of going up to 25,000 or 1 year in normal service and 15,000 miles in severe service.

Lastly, the best cure is prevention. Preventing sludge build up in your engine is critical to long engine life and best performance/fuel economy over it’s lifetime.

Using a high quality synthetic engine oil like AMSOIL Signature Series can help prevent sludge.

When using lower quality oils synthetic and conventional change oil more often.
¹ AMSOIL engine and transmission flush product is additive based and will not cause any harm to your engine or engine seals. This safe and effective engine cleaner has been tested and used for many years on all types of engines and transmissions.
² It is important to change filters at each oil change. Removed sludge will be trapped by the filter. During sludge removal, filters can be clogged. A clogged oil filter can cause engine damage. We recommend AMSOIL EaO Absolute Efficiency Filters for the best filtration and engine protection (AMSOIL Ea Oil Filters (EaO, Ea15K) have one of the best efficiency ratings in the automotive market providing a filtering efficiency of 98.7 percent at 20 microns.)

³ Download a PDF of the sludge removal procedures:

AMSOIL products are designed to be used in mechanically sound engines. Use this procedure at your own risk. We imply no warranty except as stated by the AMSOIL product warranty. AMSOIL engine flush and assorted products make no claims to fix or repair mechanical problems.
If you have any question or would like to order AMSOIL products please contact us.
Michael Sparks, AMSOIL Dealer/Direct Jobber
931-801-9401 call/text
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