Dec
21
Diesel Exhaust Fluid – FAQ
This concept is not new, and was originally patented in 1957 by Englehard Corporation.
Diesel Exhaust Fluid is one form of “cleaning” NOx pollutants from diesel exhaust. By adding a mixture of Urea and Deionized water to the catalytic reduction system you can reduce the bad stuff before it exits the tail pipe.
Ford recently sent out this FAQ on Motorcraft DEF.
FAQ
WHAT IS DEF?
A non-hazardous clear fluid (67% deionized water / 33% chemically pure Urea) that is injected into the diesel exhaust system to reduce NOx emissions.
WHY DEF?
- Required for the 2011 model year F-Super Duty 6.7L Ford diesel to meet 2010 EPA emission regulations
- For use with competitive make vehicles using a SCR (selective catalytic reduction) system
- The majority of diesel (light and heavy duty) manufacturers will use DEF to meet the new requirements
Why use Motorcraft DEF?
Motorcraft DEF is API certified, meeting ISO22241, and is the only fluid approved and recommended by Ford Motor Company. Inferior product may result in costly damage to the SCR system. System damage as a result of inferior fluid is not eligible for warranty reimbursement.
How is the vehicle filled with DEF?
The fluid is supplied through a fill port located next to the diesel fuel fill port; it has a blue cap clearly marked for diesel exhaust fluid.
What is the capacity of the vehicle DEF tank?
The DEF tanks have a five to six gallon capacity, depending on the vehicle configuration.
How frequently will DEF need to be replenished?
The system is designed to last approximately 7,500 miles between fill ups, coinciding with the oil & filter change interval. However, depending on customer use, replenishment may need to occur more frequently.
Is there a DEF tank level gauge?
The vehicle instrument cluster will provide indication of fluid level in the DEF tank, as well as provide warning messages when the DEF is low and needs to be refilled.
Can the vehicle be operated without DEF?
The vehicle will not operate properly without DEF. When the vehicle DEF monitoring system detects no DEF is available, the vehicle initially goes into a speed limiting mode and then progresses into an idle only mode.
How should DEF inventory be stored?
DEF should be stored out of direct sunlight in temperatures between 23F and 86F (-5C and 30C)
- Freezing point is 12F (-11C)
- Prolonged storage at higher temperatures will cause DEF to breakdown reducing shelf life.
- Storing DEF at 86F reduces shelf life to approximately 12months.
Can DEF freeze in the vehicle?
Yes. However, Ford Motor Company vehicles have a tank and line heater to ensure the vehicle operates in extremely cold climates.
All vehicles with equipped with an SCR utilize Diesel Exhaust Fluid. So what is an SCR any how? This image is from the Department of Energy and depicts the general process.
[Source: http://en.wikipedia.org/wiki/Selective_catalytic_reduction]