Whats up with Blue DEF?
 

Diesel Exhaust Fluid. Been frequenting this forum for a couple years now and i don't recall ever seeing much discussion on the topic.

so i'm throwing it out there.. I don't have any practical experience with the stuff but i do know generally what it is.

What is it good for?
Could a system be installed after market? Why would one want to do that?

Discussion GO!

One can reduce emissions of NOx in an emissions stream via a process called Selective Catalytic Reduction (SCR). It requires the addition of a nitrogen containing material (often urea or ammonia). This has been done for many years on powerplants, and most recently has been applied to diesel vehicles. It requires careful control of exhaust temps, so I doubt a retrofit would be easy. I think this isn't discussed much here because most of us have older cars and are trying to keep performance up and costs down.

I think Hot Rod magazine did an article on adding a DPF... they might have done one on a urea kit... not sure.

I have a dpf filter on my fuso and it has been the biggest pita since it was new. In my opinion, there is no benefit to it because the stupid thing takes 20 minutes "purging". It usually burns up 1/8 of a tank.

I don't know what it's like to NOT have the cel light on.

A DPF or urea injection system is not something you willingly add to an older Diesel. Part of the reliability of these older Diesels is that they do not have those devices attached.

Unless you are in an area where emissions laws are extremely strict and require you to retrofit such a device to your car, you should not have to worry about DEF.

The DEF fluid is for newer model Diesels and it is injected into the exhaust to make a chemical reaction to reduce certain emissions. It is the urea fluid for a urea injection system. Your urine contains urea and that is what gives pizz a certain, distinct smell. If you ride behind a bus or a truck that smells like urine/bleach, it has a urea injection system. The smell burns my nose and is very unpleasant. I personally feel that these types of emissions control devices convert one bad gas into another bad gas. It is throwing good money after bad.

The DEF is made from natural gas and deionized water, a 32% solution. The "bad gas" you smell is nitrogen and water vapor, and possibly ammonia left over from the process.

doesn't seems like DEF has many fans.

the first time i read about urea diesel exhaust fluid, i thought someone had copy/pasted an article from theonion. it's the perfect combination of muffler bearings and blinker fluid...with some pizz mixed in.

I imagine that with a properly monitored EGT probe you could get it to clean up emissions without stinking. I'll just stick to conventional methods though-intercooler and low exhaust temps

It's better than the alternative, which is more EGR, retarded timing, and more soot production. Navistar tried that route with "advanced" EGR, and it cost the president his job. They are now using the DEF process supplied by Cummins.