How often do you top up your DEF?

Oh boy....that myth again. DEF has urea in it. Just because the words urea and urine are similar, does not make it the same thing. I've worked on hog farms in the past. And I've had DEF splash back on my hand while filling. They are not, at all, the same thing. Not even filtered and processed same thing. If urine would work in a DEF tank, don't you think these companies would be telling drivers to whizz in that tank? Also, there is very little difference between human urine and hog urine. There is no magic ingredient in hog urine to make it the same as DEF.

 

https://en.wikipedia.org/wiki/Urea

Urea serves an important role in the metabolism of nitrogen-containing compounds by animals, and is the main nitrogen-containing substance in the urine of mammals. It is a colorless, odorless solid, highly soluble in water, and practically non-toxic (LD50 is 15 g/kg for rats). Dissolved in water, it is neither acidic nor alkaline. The body uses it in many processes, most notably nitrogen excretion. The liver forms it by combining two ammonia molecules (NH3) with a carbon dioxide (CO2) molecule in the urea cycle. Urea is widely used in fertilizers as a source of nitrogen and is an important raw material for the chemical industry.
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https://en.wikipedia.org/wiki/Diesel_exhaust_fluid

Diesel exhaust fluid (DEF) is an aqueous urea solution made with 32.5% urea and 67.5% deionized water.​

 

Never let it get below half or so in my road truck. Our yard truck I drive now let it get to a quater. That is because we use gallon jugs and boss doesnt like any left over. 2 jugs at quarter mark fills it up and good for about 3 or 4 days.

 

I do def every other time I fuel.

Filling 5-8 gallons of def takes about 2 extra minutes. If you have a def tank on the passenger side of the truck, more like 7 minutes.

 

I'm a company driver. My first job was local, I could technically go a week without fueling, although I only did that once as I didn't want to risk running out of fuel and only did it that once because of a problem with my fuel card. That week was about 1000 miles. I usually fueled up every other day, every day if I needed to wash the windshield. The DEF would last me upwards of a month. I didn't see any point in filling the DEF every time. If they had told me to I would have, but no point in wasting a few minutes dealing with it when I didn't need to.

Now I run regional/OTR and I have a valid reason for not doing it every time. A tank of DEF lasts about two tanks of fuel, maybe a little bit more. Our company wants us to adhere to a fuel solution. My truck has the DEF tank on the passenger side, so in order to fill it I either need to go through from the wrong side or use the DEF on the pump next to me on that side. Neither of those work very well when you are fueling at a busy truck stop. However, I usually make it to the yard often enough to only fuel at the yard, and DEF at the yard is easy.

If I'm not going to be making it to the yard, I usually keep it in mind every fuel stop, but sometimes it will run down pretty low before I find a decent spot to fill it up. I have had to get the 2.5 gallon jugs to make it a little further. I haven't let it derate yet.

 

When I was in my 388 with the Paccar MX-13, the company always wanted it filled in the yard (since they buy bulk DEF and store it on-site).

One time I went on a trip to Ontario and ran out (got low enough that the light came on, I didn't want a de-rate on the 11) on the way back after Kapuskasing (I was trying to make it to Pass Lake for the Flying J). Had to buy a 3 gallon jug in Longlac, from then on, always had that jug filled and always tracked consumption.

Shortly after that though, I got my regional position and got put back into CAT trucks and haven't missed the garbage at all. It's just a corporate make-money/jobs/laws affair that's harming the industry.

 

DEF usually pumps very slooooow. So when I had a DEF truck I would usually fill up every time I got fuel. Filling an empty DEF tank can take an impatient while.

That way I didn't have to worry about the times I was in a hurry or when DEF wasn't available. Seems like DEF pumps are out of order much more frequently than fuel pumps.

 

our fueling company tops off every day.

 

I watched a lady about 70 get on her knees and feed the def hose under her Truck
She asked me to grab it
She said she usually feeds it through the cab
Wtf?
What genius came up with a pass side def tank?
Smh