Diesel Exhaust Fluid (DEF) is an operating fluid for Selective Catalytic Reduction (SCR) technology, which is used in new heavy-duty commercial vehicles from 2010. DEF is not a fuel or fuel additive. It is injected into the exhaust system to chemically reduce NOx emissions from diesel powered vehicles. DEF is a high-purity urea solution complying with the Standards of ISO 22241. This is the highest quality and safety standard in place which ensures the correct functioning of Selective Catalytic Reduction equipment. Most engine manufacturers chose SCR over competing technologies due to the fuel economy benefits of SCR as compared with other options. Studies have shown that SCR is known to improve overall fuel economy by approximately 5%.


As governmental regulations on diesel emissions become more rigorous and complex, it has forced vehicle manufacturers to adopt new technologies in order to be fully compliant effective January 1, 2010.

DEF chart

EPA Emissions Requirements

2010 Emissions Standards for North America
Particylate Matter………………0.1g/HP-hr
This is a 98% reduction since the late 1980’s.

In order to meet the demands of EPA 2010 standards, commercial vehicle manufacturers have evaluated various engine technologies that will provide low emissions and increased performance. SCR technology or Selective Catalytic Reduction is the option many engine and truck manufacturers have chosen. In simple terms, a fine mist of emission fluid is dosed into the exhaust that reacts and neutralizes the NOx molecules. A separate tank and control unit is fitted to the SCR truck that houses the DEF fluid. The rate of consumption for the fluid is 2 to 4% per gallon of diesel fuel. Manufacturers estimate that refilling of the DEF tank will occur every other diesel fuel fill up.

Understanding DEF image

Selective Catalytic Reduction (SCR) is one of the most cost-effective and fuel-efficient diesel engine emissions control technologies available. It allows passenger cars and light duty trucks meet strict mandated emissions and fuel efficiency guidelines without compromising power and performance.

In the commercial trucking industry, the ability to reduce emissions to near-zero levels while attaining 3-5% diesel fuel savings is good for business and the environment! This clearly distinguishes SCR as one of the premiere emissions-control technologies for our customers.

How SCR SYstem works image diagram

Estimate your DEF usage at a glance with our usage chart or use our calculator for a more precise estimate of your unique needs.

DEF Usage Chart



Maintaining Diesel Exhaust Fluid (DEF) product integrity is vital to the efficient and long-term operation of Selective Catalytic Reduction (SCR) system-equipped vehicles. In order to provide the very best in product purity, PPC DEF SOLUTIONS handles and delivers BlueDEF™ and Drydene DieselALL® DEF via “Closed Coupler Systems” (“closed”).

In a “closed” system, containers have a valve coupling system that seals the container opening on Drums, Totes and Bulk tanks to prevent dirt, debris, and other contaminants from entering the container and contaminating the DEF fluid. This system helps keep the product as pure as when it was blended at the plant.

PPC offers a variety of proven and reliable storage and dispensing equipment that can be customized to your specific needs. Our “closed” system equipment products ranges from drum systems to remote stand-alone systems that are insulated and can be placed on Fuel Islands. In addition, PPC will custom build any DEF storage and dispensary system to meet your specifications. Businesses can also take advantage of our reasonable lease-to-own and loan equipment programs for eligible applicants.



Diesel Exhaust Fluid or DEF is a high purity chemical solution containing 32.5% urea and 67.5% deionized water.

Urea is the active ingredient of DEF. Urea is created from synthetic ammonia and carbon dioxide when subjected to high heat and pressure and can be produced as a liquid or solid. Synthetic urea is used mainly in fertilizers but is also used in plastics, animal feed, cleaning agents, and pharmaceutical applications.

Diesel engines are required to meet stringent emissions requirements in 2010. Many diesel engine manufacturers have chosen a technology called Selective Catalytic Reduction (SCR) to meet these requirements. When added to the exhaust gases Diesel Exhaust Fluid reduces the NOx to the EPA required levels. If you purchase a car, truck, tractor or any diesel powered product with SCR technology it will require DEF.

No. This is a typical misconception. DEF is a fluid that is atomized into the exhaust stream after it leaves the Diesel Particulate Filter and before it enters the Selective Catalytic Reduction system. In the SCR catalytic converter the ammonia molecules treat and neutralize the NOx molecules converting them to Nitrogen and Water.

No, DEF is classified as a non-hazardous product.

The consumption rate of DEF is between 2-4% of the diesel fuel consumption. For example, for every 100 gallons of diesel fuel consumed, between 2 and 4 gallons of DEF will be automatically injected into the exhaust system. The typical DEF tank will be approximately 15 – 20 gallons, thus requiring a fill every 5,000 to 6,000 miles.

Yes. Storage temperature between 40°F and 80°F is recommended to maintain product shelf life. Storage temperature above 12°F is recommended to avoid crystallization which starts at 11°F. Prolonged storage above 86°F will cause hydrolysis to occur, with the consequent formation of ammonia and pressure rise, and will reduce shelf life and product effectiveness.

Yes. The shelf life will depend on the temperature at which product is stored, however product older than one year is not recommended to be used.

Diesel equipment has heated tanks and supply lines that are designed to freeze and thaw with no performance issues.

No, the DEF solution has been formulated so that when thawed after freezing it will not separate or lose performance characteristics/strength.

Cost can depend on a variety of factors. Please contact your local sales representative or call 800-772-5823 to talk to a PPC Lubricants Customer Service Representative.

In addition to reducing NOx emissions, the use of DEF and SCR technology will typically result in improved fuel mileage for most vehicles. The amount of improvement will vary based on your equipment. Many in the industry feel that 3 – 5% improved fuel economy will be realized using DEF and SCR technologies.

If you are truck driver, DEF will be available at many of the locations where you buy diesel fuel. If you have a fleet, PPC Lubricants Inc & PPC Terminals can provide DEF in a variety of package and dispensing solutions that meet your needs.

DEF is stored in dedicated containers (must be stainless steel or poly tanks) and dispensed through highly specialized dispensing units. Using substandard equipment can contaminate the DEF and subsequently poison the SCR Catalyst.

DEF is manufactured to strict ISO 22241, AUS 32 and DIN 70070 standards. These standards ensure proper manufacturing, testing and handling procedures. DEF should only be purchased from companies that provide proof that they follow these standards.



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