| two travelers 
  Smithtown, NY
 
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 | We have a 2023 Winnebago View on the Sprinter chassis. Currently have about 1/2 tank of DEF and plan to top off before storing for the winter. I have some DEF in the basement with a manufacture date of May. Is it safe to use this or should I buy fresh? We will likely use the coach again in March next year. From what I've read it might be OK but would like some real world opinions.
 
 
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								| Trackrig 
  Spent the summer in Conconuly, Wa, MH now in Vanco
 
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 | All sorts of people are going to leave it sitting in their equipment that will sit idle for at least the winter.  Farmers, dirt people, truckers, etc.
 
 Bill
 
 
 Nodwell RN110 out moose hunting. 4-53 Detroit, Clark 5 spd, 40" wide tracks, 10:00x20 tires, 16,000# capacity, 22,000# weight.  You know the mud is getting deep when it's coming in the doors.
 
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								| enblethen 
  Moses Lake, WA
 
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 | From DEF facts
 
 16. What is the shelf life of DEF?
 If the DEF is stored at ambient temperatures of 75 F with no major periods of exposure to heat over 86 F then the batch of DEF will last roughly two years. If a package of DEF is exposed to periods of heating the fluid will last approximately one year.
 
 
 Bud
 USAF Retired
 Pace Arrow
 2003 Chev Ice Road Tracker
 
   
 
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								| Grit dog 
  Black Diamond, WA
 
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 | It’s not gasoline, so the topping off theory (also flawed when considering gasoline) does not apply.
 
 
 2016 Ram 2500, MotorOps.ca EFIlive tuned, 5” turbo back, 6" lift on 37s
 2017 Heartland Torque T29 - Sold.
 Couple of Arctic Fox TCs - Sold
 
 
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								| ScottG 
  Bothell Wa.
 
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 | One thing is for sure, you do not want to put bad DEF in it.
 
 
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								| eHoefler 
  ozark mountains
 
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 | What till spring and top off with very fresh DEF.
 
 
 2021 Ram Limited, 3500, Crew Cab, 1075FTPD of Torque!, Max Tow, Long bed, 4 x 4, Dually,
 2006 40' Landmark Mt. Rushmore
 
 
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								| way2roll 
  Wilmington NC
 
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 | I know the manufacturers say it has a shelf life, of course they want you to buy more DEF. But I have never heard of any actual issues with someone using old DEF. Lots of theories and warnings but I have never read of a documented case. It's urea and water and gets atomized into the exhaust. And are you going to drain the DEF in your tank in the spring? Isn't it probably just as old?
 
 
 2023 FR Sunseeker 2400B MBS
 
 
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								| dalej 
  texas
 
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 ScottG wrote: One thing is for sure, you do not want to put bad DEF in it. 
 This
 
 
 2005 Chevy HD2500, ext cab, 4x4, 8.1, allison,lwb,srw, 265 75 16's, timbrens
 
 
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								| way2roll 
  Wilmington NC
 
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 dalej wrote: ScottG wrote: One thing is for sure, you do not want to put bad DEF in it. 
This 
 What happens? Do you have an example of using "bad" DEF? And how do you tell if it's bad?
 
 
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								| mike-uswest 
  Central Point, OR, USA
 
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 ScottG wrote: One thing is for sure, you do not want to put bad DEF in it. 
 I liked it a lot better when I didn't have to use any DEF.
 
 
 2019 Ram 2500 TCD, 4X4,
 Arctic Fox 25Y 30'
 
   
 
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