DEF?

The Volvo DPF/SCR system seems to have the right idea. Its designed to not run active regenerations under normal operating conditions.

 

You own one? What year? Average MPG Bestto worst? Thanks

 

The more you idle the more you will need to regen? If so that might explain why I haven't had to regen my Cascadia in 5 months, I hardly idle.

 

SAY WHAT?? The DEF system has nothing to do with the Diesel Particulate Filter or the regen system! The exhaust fluid is called a SCR strictly added to reduce oxides of nitrogen also known as NOx.

 

Company truck. 2011 Volvo 780 sleeper. Averaging 6.6 right now thanks to lugging heavy wagons. Best was averaging nearly 10mpg bobtailing from El Paso, TX to Jefferson City, MO. Worst I'd say was 5.9.

 

Here's what is going on when your truck uses DEF:

"Selective catalytic reduction is used to reduce the amount of NOx#released into the atmosphere. Diesel exhaust fluid (from a separate DEF tank) is injected into the exhaust pipeline, the aqueous urea vaporizes and decomposes to form#ammonia#and carbon dioxide. Within the SCR#catalyst, the NOx#are catalytically reduced by the ammonia (NH3) into water#(H2O) and#nitrogen#(N2), which are both harmless; and these are then released through the exhaust."

Volvo takes it one step further and uses the NOx to oxidize the soot passively in the diesel particulate filter which occurs at a lower temperature than is needed with a conventional active regeneration system. Volvo figured if they were going to be tackling the NOx downstream of the DPF with the SCR, they might as well tweak the engine to reduce soot, which increases NOx and then use that NOx to clean the DPF instead of running active regens.

 

That takes care of THAT!

 

yah if ya run out just piss in the tank

 

Yep... that'll really work well. NOT!!!