Def Consumption

I always figure about 1gal for every 100miles.

 

Normal? No, id say that was pretty good. Needle should be just above 1/4

 

I've got a 16 Cascadia with a Detroit and it's consumption on this week was 13 gal of DEF after almost 400 gal of fuel.
That was at 3200 miles. Mine may be the exception to the rule, but it's typical for MY unit.

 

Ya that is probably right where it should be. Fill it up from the pump don't let it run out. You should get anywhere between 120 to 200 mpg on def.
Friend of mine used to drive similar trucks, Volvo with ishift and def, said it barely uses any in warm weather but in colder weather it takes more. Might be a Volvo thing. Point being just keep it full and as long as you don't have any error codes you are good to go.

 

Sounds about normal. The more fuel you burn the more DEF you use. Plus different trucks can have difference size DEF tanks

 

It's directly proportional to fuel economy.
Have a light load with a tail wind. It won't use much.
Have a heavy load on a windy day, it will use more.
It will use more in the winter.
I use about 25 gallons a week in the winter, and about 15 gallons a week in the summer. Averaging about 2,200 miles a week pulling 140,000 lbs.
2016 Cascadia DD16 600hp.

 

APU. Or hotel.

 

2015 cascadia, I'm averaging 304mpg for def over last 120k miles