Tuesday, June 14, 2016

Adding Some DEF to the Fuse

The Fuse now has a little over 4000 miles on the odometer. I have gotten in the habit of checking the information center  when I start up to see if there are any errors showing or anything else interesting.  One menu is DEF Level.   On our last trip I had a message.

Winnebago Fuse DEFWinnebago Fuse DEF

DEF Level Under 1/2 full.   Newer diesel vehicles require an emissions additive called DEF.   DEF stands for Diesel Exhaust Fluid and is a refined urea solution.  

From the Ford manual when the DEF gets down to where it thinks it has 500 miles left to go it will show as a warning.  But why wait?  I fill up the fuel at 1/2 a tank, I might as well fill up the DEF at the same level and not worry.

First thing is to get some more DEF.  You can buy DEF at the pump at many larger diesel stations or you can get it at most places that sell auto supplies.  So how much do I need? Well the manual says that the DEF tank holds 5.5 gal.  So 2.5 gal should be enough to bring it from 1/2 to close to full.

Winnebago Fuse DEFWinnebago Fuse DEFWinnebago Fuse DEF

So what type should I buy?  DEF is DEF and so long as it if from a trusted vendor you should be good.  I read over the front and back labels to verify it was standard DEF.  As the label says OEM approved.  The other thing I looked for is when it was made.  I have heard it goes bad sitting in the heat after a year or so.  I wanted to make sure I got some that was fresh.   This was on the label and was a month old so I was good there.

So I purchased the Walmart house brand and they had a 2.5 gal container of it so I was set.  It even came with a spout to make adding it easy.  Another plus for this brand.  It was also $7.88 for 2.5 gallons.  The Peak BlueDEF brand was $5.99/gallon so this was the least expensive option as well.

Winnebago Fuse DEF

Now it was time to add the DEF to the Fuse.  Well under the Diesel fill is a blue screw on cap covering the DEF fill.  You unscrew the cap and pour it in.  The nozzle that came with the DEF made this very easy and I only spilt several drops.

Once I finished filling the DEF I cranked up the engine and looked at the messages again.  After a minute or so the DEF message changed to OK.   I think it was a success.


  1. How many mile do you get on a gallon of fluid or in this case 2 1/2 gallons

  2. Well we got ~4000 miles on 2 1/2 gal of DEF so that makes it roughly 1600 miles per gal of DEF. At 7.88/2.5 gal that equals $0.002/mile in additional cost. I have been getting around 15 miles per gallon of diesel fuel . So that means that if you are adding everything up add an additional $0.03/gal of diesel to cover the cost of the DEF. (if I got the math right)