DEF Usage high?
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DEF Usage high?
I just completed my first 1000 miles on my 2017 F350 SD 6.7 and the DEF gauge is reading half full. I'm new to the whole DEF deal but from what I have read that seems a bit excessive. IDK? is that in line with what others are experiencing? Thanks for your reply's
Dave
Dave
Cargo Master
Joined: Feb 2008
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From: Tooele, UT
I can go about 6K on a tank so to me that seems a bit excessive. BUT, I don't tow and it's almost all highway driving so my usage will be less than someone who tows. How are you using the truck?
Hotshot
Joined: Oct 2015
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From: Wyoming
Dave, I think my usage is close to yours. I pull a 11k (gvwr) toy hauler in the mountains. I have about 3800 miles on mine and have added two jugs of DEF (5 gallons total). My DEF gauge shows a bit below full right now.
Cargo Master
Joined: Dec 2003
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From: Central MO
Dave, your usage seems a little high to me. I've got 6700 miles on my truck and I've used 10 gallons (just added my 4th 2.5 gallon jug and it filled it to the top). On a recent trip of 2500 miles (2000 towing our 9500 lb fifth wheel), I used just over half a tank.
Hotshot
Joined: Nov 2013
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From: Hempstead, TX
Bear in mind too that the DEF tank is not completely filled at the factory, and if the dealer fails to do so before delivery, it will appear to use more than it does. If you KNOW the dealer topped it off before you took delivery, and you're not towing a bunch, that is excessive use.
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I am towing a 44Ft race trailer, but didnt figure it would use that much in 1K miles, and The gauge read full at the dealer when I picked it up, but not sure if it was totally topped off. Well if this keeps up, gona go broke buying DEF! Where's my old trusty 6.0 when I need it! LOL
Hotshot
Joined: Nov 2013
Posts: 10,107
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From: Hempstead, TX
Because of the way the sensors in the tank work, it can read full, even when not topped off. Let the level get down to the mileage countdown, then fill completely. See if that doesn't improve your indicated useage.
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Joined: Aug 2016
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From: Olympia, WA
I too would say it's most likely just an incomplete fill of the DEF tank. There have been a number of people report this issue, and it seems to often point back to something the dealer missed on the prep. From the factory there is only about 1 gallon, then the dealer should add the other 4ish during prep.
I have noticed with my tank, I can get a 1/2 reading even when only about 2 gallons down. So even if they only shorted you a small amount, it could still quickly go from full to 1/2. I would recommend filling it (use the motorcraft tube or an actual DEF pump), and check again in another 1000 miles.
If it's worth your time you can always go back to the dealer and see if they will do it for free.
I have noticed with my tank, I can get a 1/2 reading even when only about 2 gallons down. So even if they only shorted you a small amount, it could still quickly go from full to 1/2. I would recommend filling it (use the motorcraft tube or an actual DEF pump), and check again in another 1000 miles.
If it's worth your time you can always go back to the dealer and see if they will do it for free.
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Brett Foote
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Joined: Mar 2016
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From: Long Island
I had a similar concern. I was using 5 gal of DEF every 4900 miles. Did an under truck inspection and found white crystals around the DEF Reductant Injector indicating a leak. Took it to the dealer today and they agree it is leaking. They ordered an entire new pressure line and injector. Should have the truck back tomorrow. Under warrantee.
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From: Frederick, MD
I too think it was not full upon delivery. Very common actually.
I would wait till you are around 200 miles to empty before filling. Then do a complete fill up. Less confusion for the system.
I would wait till you are around 200 miles to empty before filling. Then do a complete fill up. Less confusion for the system.
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