How much def can you put in??

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KX5jeron

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Like the title says, this truck is new to me, 2015 Ram 2500. But I've been adding 1 box of def (2.5 Gal) when the light comes on because I have read that problems can happen if you overfill them. Freezing in the fill neck or something like that. I live in Utah so it gets down around 0 sometimes in the winter.

could I put 2 boxes in when the light comes on?? or what about filling it until it is full?? No real good info about filling these and if you can put to much in..
 

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Is there a Level line on the inside or outside of the tank, is there a dip stick, there has to be something to know the level of the tank.
 

crash68

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The tank hold 5 gallons, DEF doesn't freeze until below 12°F. There's expansion room for the DEF to expand when it slushes/freezes.
 
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KX5jeron

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The tank hold 5 gallons, DEF doesn't freeze until below 12°F. There's expansion room for the DEF to expand when it slushes/freezes.
Do you know how much is left when the def light comes on?? because 2 boxes would be 5 gallons..
 

WY-Dave

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https://www.mopar.com/en-us/my-vehicle/vehicle-information.html?redirect=om

Click select a vehicle, fill it out
then go to supplements and more
then choose diesel supplement


p. 315 DEF tank 2015 2500/3500 is 5.5 gal. The general consensus is at the half mark put in the 2.5g def. Then you never will over fill

I did Blue Def for the first fill then switched to WallyWorld's version. There was some concern that WW Def is not good enough. I bought a refractometer to verify the correct mix. I have only had it for the last jug I bought and it tested fine. Some jugs have a lot date, this way you can tell if it is "fresh". Being $5 cheaper than Blue Def, there is a way better chance that the WW DEF has not been sitting around.

From Peak
The quality of DEF also is not affected if the fluid freezes. When stored under optimal conditions — between 12°F and 86°F — DEF has a shelf life of up to two years. If stored in warmer temperatures, shelf life decreases.

https://www.peakhd.com/lifeblood/fl...lso,warmer temperatures, shelf life decreases.
 

rixter99

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Is there a Level line on the inside or outside of the tank, is there a dip stick, there has to be something to know the level of the tank.
No, it's near the fuel tank, and fills thru the fuel door...Only gauge is the DEF gauge on the instrument panel...
 

GTyankee

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At Wally World i buy the SuperTech DEF
You will find it in the Automotive section.

Never buy DEF if the store stacks it up in front of a window or near a heat source, it shortens the shelf life drastically.

The Supertech DEF sells fast at WW
Supertech DEF manufacturing date is on the front of the 2 1/2 gallon jugs

I find it strange the Ram 1500 w/ Ecodiesels DEF tank holds 8 gallons if i recall correctly.
You would think that the 2500 DEF tank would be larger than that
 

Earl Zeis

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As said it's a 5 gallon tank. When mine hits half a tank I put in a 2.5 jug and done. No worries of running out or overflowing it.


Earl
 

Gr8bawana

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I usually run mine down until the needle hits the red on the gauge. I put in a 2.5 gal jug and it brings the gauge up to about 3/4.
I don't know how low it would have to get to be able to add 5 gallons .
1126191022-00.jpg
 

RamItFaster

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I fill DEF at the local truck stop, yeah it's a pain in the ass but they cycle through it so fast I'm not worried about it being too old. I have never spent 10 dollars filling up my DEF tank because I never let it get under half. Why buy in a box and try to juggle it I say lol
 

chri5k

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Every time I have tried to put 2 jugs (5 gal) in it has overflowed. There was about a quart of fluid left in the jug. Both times I ran it down until the message on the dash said 50 miles until limp mode. Now I just wait until it is in the red and put in 1 jug when I get around to it.
 

BWL

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A jug at a time when the light comes on is the best way in my opinion, but as long as it's above freezing temp overfilling it is harmless. Just a plastic tank with a pump in it. The other benefit of keeping less in there in the winter is the def heater will get it thawed faster so less chance of it going into limp mode because it's not getting fluid.
 

OLEJOE

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On my 18’ 2500 I wait until it gets down to 1/4 mark and add 2.5 gallons. Brings it almost up to the full mark. Plenty in it but not too full. I like for it to have a little sloshing room.
 

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I found a spectrameter(SP), it checks for the right mix ration. 3 jugs since getting it it of wally world DEF and right on the money each time
 

Sandevino

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A guy I know buys his DEF from the dealership and keeps his receipts along with his DEF fill records. He ran into DEF system issues and the dealer blamed bad DEF until he produced his records.

Warranty covered everything 100%.
 

Gr8bawana

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I put in a 2.5 gallon jug just before towing the TT on a fishing trip. The gauge right at half full. I was surprised it took the entire jug but it took the gauge all the way up to just past full. Only use a 1/4 of the DEF tank so I'll be good for a long time.
 
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