Diesel Exhaust Fluid Poor Quality Warning alert. What to do?

Shoot, didn’t even know that.

 

Still a valid subject..

I want to know what exactly qualifies or makes the DEF "poor quality" .. non OEM??? hehe

 

SCR system is malfunctioning or the DEF filter needs to be replaced. I’m not sure what the average maintenance time for def filters is. But def or scr can and will cause engine failure.

I still remember talking to a guy back in 2014. We were at a freightliner dealer in Utah. His engine failed, the dealer couldn’t find the problem so they proposed on rebuilding the engine. The last thing he saw on his dash was that “def poor quality” warning. And this was on an automatic transmission with 255k miles.

 

(Going off memory, so i could be wrong on specifics, but the concept is valid.)

DEF is 37.5% urethra, and the res distilled water. If those percentages are off either high or low it will cause errors. This is why def needs to be heated in the winter.

Of course like most errors for emissions it may have nothing to do with def. I had a truck getting this error and it ended up being the dpf was clogged up.

 

Once DEF changes from its normal ratio of urea and water it is no longer "good quality". Just because you bought it from a big chain doesn't mean its good.

Most emission systems are actually disabled upon engine start up below a certain temperature until the DEF is thawed out and warmed up. If it isn't thawed out in x amount of minutes, the system detects a problem and starts generating fault codes.

 

Thank god we did not fool with that crap in our time.

Im sorry I just have to vent. I was thinking crappy DEF, find another source.

I best be quiet from here on out, it's amazing when a big truck computer complains it's being maintained on a beer budget rather than a champagne taste.

 

I don't let the DEF get too low, for the same reason I don't let the fuel get too low: if you get watery fuel/def, it is now most of what is in your tank. You have a better chance of weathering bad fluids if your putting less in.