Water in DEF tank?

Discussion in 'Ask An Owner Operator' started by MakinMovesFast19, Feb 9, 2020.

  1. MakinMovesFast19

    MakinMovesFast19 Bobtail Member

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    Have anyone here ever heard of using water in the DEF tank? Is this safe to do?
     
  2. Mid-May Trucker

    Mid-May Trucker Road Train Member

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    No it has sensors that tells what the liquid is made of.
     
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  3. RockinChair

    RockinChair Road Train Member

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    It will cause your engine to de-rate or shut down.
     
  4. AModelCat

    AModelCat Road Train Member

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  5. Ridlingdj

    Ridlingdj Medium Load Member

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    It will work about as well as using water in your fuel tank
     
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  6. mhyn

    mhyn Road Train Member

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    not all trucks have that sensor.
    if scr is bypassed you can use distilled water.
     
  7. AModelCat

    AModelCat Road Train Member

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    Will the lack of NOx conversion thru the catalyst not be picked up when the aftertreatment control module compares inlet vs outlet NOx? I know some did it that way prior to 2018 when DEF quality sensors became mandatory.
     
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  8. Roberts450

    Roberts450 Road Train Member

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    Just incase ya don’t know DEF is 32.6% urea and 67.4% water.
     
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  9. mhyn

    mhyn Road Train Member

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    let outlet nox sensor sniff clean air. Nox conversion is 100%. you can put water in def tank..
     
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  10. Freddy57

    Freddy57 Road Train Member

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    They use deionized water to prevent the nitrogen molecules from binding themselves to other molecules. Straight water will cause problems with the distribution. The new trucks get errors from it.