Small DEF Tank
Cargo Master
Joined: May 2012
Posts: 2,616
Likes: 1,190
From: Door Cty/Florida
I've never wanted a larger DEF tank. I could fill my tank at every oil change (5-6,000 miles) and would never run out. Plenty of warning messages too when you get low.
When I purchased my truck I had a concern about DEF but a post on FTE told me to fill the tank and don't worry about it. The person that made this post is correct. I never worry about DEF or carry extra now that I've had the truck 2.5 years and 28,500 miles. Every few months I go out and see how much I can fit in the tank. Then I forget about it.
When I purchased my truck I had a concern about DEF but a post on FTE told me to fill the tank and don't worry about it. The person that made this post is correct. I never worry about DEF or carry extra now that I've had the truck 2.5 years and 28,500 miles. Every few months I go out and see how much I can fit in the tank. Then I forget about it.
Posting Guru
Joined: Dec 2008
Posts: 1,226
Likes: 5
From: Rusty, Maine
Yeah. Don't worry about it Dave. I can haul 5 small cars on one trailer (grossing nearly 30,000 pounds) all the way from NH to OR and fill it when I leave NH, fill it when I get to OR. (2014 F-450) And even then I've got some miles to go.
It warns you when you have 500 miles to empty. And if you're ever curious, you can check the status of the tank at any time through the cluster.
And if you're STILL worried about it then you can swap in a Chassis cab tank at 6 gallon cap. Although I'm not sure that this is a R and R swap...
It warns you when you have 500 miles to empty. And if you're ever curious, you can check the status of the tank at any time through the cluster.
And if you're STILL worried about it then you can swap in a Chassis cab tank at 6 gallon cap. Although I'm not sure that this is a R and R swap...
Senior User
Joined: Aug 2012
Posts: 274
Likes: 0
From: Waco, Tx
I've never worried about DEF in my '12... After reading all the horror stories about trucks shutting down and whatnot I decided to run a test and see how many miles I get from full to the first 1/2 full warning.... so far 4900 and change miles and counting... That's a fairly even mix of town, highway and towing a 12K 5'er...
Logistics Pro
Joined: Oct 2010
Posts: 3,596
Likes: 63
From: Texas
The more you tow, the more DEF you use. Towing through the Smokey's for a few weeks had me using quite a bit of DEF. I just refilled at the Pilot stations in the Big Rig fueling as they have DEF at the pumps.
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Senior User
Joined: Jan 2013
Posts: 238
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From: Northern New Mexico
Ditto here. I have never received the next message after "less than half full."
Lead Driver
Joined: Jan 2010
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Funny.
Posting Guru
Joined: Dec 2008
Posts: 1,226
Likes: 5
From: Rusty, Maine
10 characters
Lead Driver
Joined: Nov 2005
Posts: 8,456
Likes: 4,952
At least the low DEF warning gives you 500 miles advance notice of the tank being empty. I am always able to get to a DEF pump well before running out.