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best def fluid

What is Diesel Exhaust Fluid (DEF FLUID) and who needs it?

best def fluid

Diesel Exhaust Fluid (DEF) is a urea-based fluid specifically engineered for diesel engines as the reducing agent in Selective Catalytic Reduction (SCR) systems, which is a new vehicle technology platform for reducing NOx emissions through exhaust aftertreatment. DEF is a solution made up of purified water and 32.5 percent urea that is used as a carrying agent for the ammonia needed to reduce nitrogen oxide (NOx) emissions from diesel engines into nitrogen, water and carbon dioxide (CO2).

When coupled together using the exhaust fumes, then it transforms the poisonous nitrous oxide to ammonia and carbon dioxide that are two gases that are manageable. Greatest Diesel Exhaust Fluid (DEF) Reviews: Unless you have driven a significant diesel truck, then the expression DEF or an exhaust fluid will most likely be unknown.

Diesel Exhaust Fluid (DEF) is a non-toxic, clean, and colorless energy controller liquid that is required for modern-day diesel motors. The liquid is pumped into the exhaust flow rather than the gas pipeline. Best-diesel-exhaust-fluid-(def)-testimonials Basically it smells such as a cleansing agent with a small odor of ammonia. Diesel technology along with the motors themselves have seen a significant increase in clean surgeries over the past several decades. This growth can be directly credited to the 2010 EPA regulations.

Several industries throughout the planet, have benefited from advanced diesel layouts and cleaner operations. This directive led to produces providing improved low-sulfur fuels and technical converters to curtail the poisonous nitric oxide exhaust gases. An important advancement in diesel technologies has been the accession of DEF.

Why do I need DEF?

Since the enactment of lowered NOx standards by the EPA on January 1, 2010, all of the leading heavy-duty diesel engine manufacturers have been installing the Selective Catalytic Reduction (SCR) systems on the vast majority of their engines. With this modification, a routine addition of the Diesel Exhaust Fluid (DEF) is required to keep the engine running. Cooper Petroleum Inc. has acknowledged the rising demand for DEF and partnered up with its leading manufacturer AirBlueFluids Inc (ABF) to fulfill your needs for this additive.

It’s over the past couple of years that diesel technologies have seen a significant shift — rugged layout and much better fuel proficiency. This type of directive, then, forced the producers to furnish specialized exhaust fluids therefore nobody needs to cough around that shameful and bloated unpleasant smoke if they would be supporting a truck (or essentially any diesel-run automobile ). Because that is what DEF was created to remove and it absolutely still does the work.
Additionally, here would be the finest Diesel Exhaust Fluid (DEF) reviews in order to understand which product do exactly what and how it’ll be useful for your type of wants.

All of this listing can be found on Amazon so that you can conveniently purchase the exact identical directly from the comfort of your house. Within the following guide, we’re likely to breakdown the very ideal DEF liquid for various popular diesel engines available on the market. Let’s begin!

Top 4 BEST DEF FLUID updated 2021

#1 Best DEF Fluids

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The business boasts of complete bulk distribution centers. From drum to a comprehensive distribution system. BlueDEF is on everybody’s radar in regards to picking the ideal solution. Peak Commercial and Industrial Products started business in 1973 in the summit of a petrochemical deficit.
BlueDEF adheres to the ISO 22241 regular and can be API accredited. BlueDEF utilizes artificial urea using the smallest of impurities Together with deionized water
Popular manufacturer and producer of diesel exhaust liquid using a product supplied at a fantastic price.


  • Successfully produces secure nitrogen gas and water vapor out of NOx in gas.
  • This item meets all EPA regulations concerning Selective Catalytic reduction engines.
  • Provides you with a fantastic price versus additional DEF choices.
  • Ships using a tube so it is possible to add the item to the DEF container securely.
  • Clients with distinct automobile types advocate BlueDEF.


  • Container seals might be better.
  • Jug may flow if a tube isn’t connected correctly, which means you can want a connection.

#2 Prestone HD 1001 Command DEF

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Prestone is identical to quality automotive goods.Their DEF adheres to all political regulations . Operators could expect to observe that the Prestone brand of goods at each truck stop and automotive store throughout the world. Prestone DEF can be used with modern SCR systems. Uses only the maximum quality materials to guarantee compatibility with federal emissions requirements.


  • Worldwide brand .Works as advertised to maintain Selective Catalytic reduction petrol motors.
  • Includes all the certificates necessary to get a product similar to this.
  • Properly equipped container means that you don’t need to worry about leaks. Reputable brand.


  • Could not be acceptable for most diesel engines and may trip a motor code.
  • A bit more costly than another DEF products within this jar size.

#3 Best DEF Fluid for Duramax

You need to be understanding that there are various brands in the current market situation that promise to create the highest high-quality diesel exhaust fluid. The massive number of brands may further cause confusion. Let us take a peek at them.

Genuine GM Fluid 88862659 Diesel Exhaust Fluid

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The ACDelco DEF fulfills every strict principle for purity. DEF will have to get refilled about every 1000 miles of usage. The Duramax line advocates using just ACDelco DEF to their motors. This GM DEF is especially created for Duramax engines. Will meet essential requirements for several General Motors diesel engines, however it is a little more costly than a few other DEFs. ACDelco provides a whole line of electrical components and fluids.


  • ACDelco has a long Record of OEM Role Fabricating for General Motors
  • Compatible with almost any GM manufacturer
  • Works with Selective Catalytic Reduction methods of General Motors vehicles such as heavy duty trucks and trucks. Reduce NOx emissions. Compatible with older versions dating back to 2010. Made by means of a brand that’s trusted by General Motors owners.


  • Could be a little expensive if bought in 1 minute increments
  • Costly, particularly considering you get one gallon to get the purchase cost.

#4 Best DEF Fluid for Ford PowerStroke

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Motorcraft is Currently a decade Extended partner of Ford Motor Company.Motorcraft includes a extensive line of automotive goods made by Ford in your mind. Motorcraft DEF is devised to operate for almost any Ford Diesel motor and several competitors.
Despite some excellent control issues, this DEF is a fantastic selection for both Ford owners.


  • First OEM product
  • Made specially for Ford diesel-powered automobiles. Meets all necessary criteria for handling NOx emissions in heavy duty gasoline engines. Nozzle was made to reduce spills and messes throughout program.
  • Motorcraft DEF won’t create any automobile warranty problems.


  • Packaging and seals could be better

DEF: Properties & Handling Guidelines

Q. What is Diesel Exhaust Fluid (DEF)?

A. DEF is the reactant necessary for the functionality of the SCR system. It is a carefully blended
aqueous urea solution of 32.5% high purity urea and 67.5% deionized water.

Q. What is urea?

A. Urea is a compound of nitrogen that turns to ammonia when heated. It is used in a variety of
industries, including as a fertilizer in agriculture.

Q. How will I know that the DEF product I purchase will work?

A. The DEF you purchase should state and display the certification of the American Petroleum Institute
(API), German Institute of Standardization DIN70700, the International Organization for Standardization
ISO 22241-1, and meet AUS – 32 specifications. This will ensure the proper purity and concentration
(32.5%) of urea. For more information on these specifications, visit www.iso.org.

Q. Can I make DEF myself?

A. Cummins Filtration does not recommend customers make DEF themselves. DEF has strict
requirements for maintaining concentration and purity of ingredients that is critical to the proper
functioning and longevity of the SCR system.

Cummins and other OEMs require that DEF used with their
SCR systems meet all ISO22241 specifications as well as API certification requirements. It is
recommended that end users purchase certified DEF and avoid blending it themselves. For more
information about the quality standards, refer to ISO22241 which details specifications for DEF quality,
handling, testing, transportation storage, and refilling.

Q. What is API Certification?

A. API Certification is a voluntary program established by the American Petroleum Institute (API) which
certifies and monitors that diesel exhaust fluid meets ISO specifications. The program was launched in
March 2009. Cummins Filtration DEF currently meets ISO specification and is also API certified.

Q. What is the freeze point of DEF?

A. A 32.5% solution of DEF will begin to crystallize and freeze at 12 deg F (-11 deg C). At 32.5%, both
the urea and water will freeze at the same rate, ensuring that as it thaws, the fluid does not become
diluted, or over concentrated. The freezing and unthawing of DEF will not cause degradation of the

Q. Does DEF expand when frozen?

A. Yes, DEF expands by approximately 7% when frozen. DEF packaging and tanks are designed to allow
for expansion.

Q. How much does DEF weigh?

A. DEF weighs approximately 9 pounds per gallon.

Q. How do I keep the DEF from freezing? What happens if the DEF freezes
in the tank on the vehicle?

A. During vehicle operation, SCR systems are designed to provide heating for the DEF tank and supply
lines. If DEF freezes when the vehicle is shut down, start up and normal operation of the vehicle will not
be inhibited. The SCR heating system is designed to quickly return the DEF to liquid form and the
operation of the vehicle will not be impacted. The freezing and unthawing of DEF will not cause
degradation of the product.

Q. Can an anti-gelling or freeze point improver be added to the DEF to
prevent it from freezing?

A. No. While an additive could improve freeze point of the mixture, the 32.5% solution is very specific to
providing NOx reducing properties. Any further blending or adjusting of the DEF mixture will impede its
ability to perform correctly and may cause damage to the SCR components. Additives of any type are not
approved for use in DEF today. If the ISO standards should change to allow antifreeze additives,
Cummins Filtration will ensure our product continues to meet ISO requirements.

Q. Are there special storage requirements for DEF?

A. DEF should be stored in a cool, dry, well-ventilated area, out of direct sunlight. While the optimum
storage temperature is up to 77 deg F (25 deg C), temporary exposure to higher temperatures has little to
no impact on the quality of DEF.

Q. What is the shelf life of DEF?

A. The shelf life of DEF is a function of ambient storage temperature. DEF will degrade over time
depending on temperature and exposure to sun light. Expectations for shelf life as defined by ISO Spec
22241-3 are the minimum expectations for shelf life when stored at constant temperatures. If stored
between 10 and 90 deg F, shelf life will easily be one year. If the maximum temperature does not exceed
approximately 75 deg F for an extended period of time, the shelf life will be two years.

Further Reading : Is Def Fluid Made From Urine? Things To Know


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