DEF Warning in F350

RedRocket204 wrote:
I see nothing where Fish says DEF does not degrade...in fact, he says he does understand it does degrade -->

FishOnOne wrote:
yes we all know that the shelf life is reduced with elevated temperatures

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The point he was making is that it seems GM is more sensitive to degraded DEF...pretty easy to read and understand that was his point.

Here is a document about DEF degradation: https://www.fcsdchemicalsandlubricants.com/main/additionalinfo/DEF%20Shelf%20Life%20and%20Fluid%20Quality.pdf

DEF document wrote:
EXAMPLE: In 2009 the two hottest months in Phoenix Arizona were July and August. The average temperature for both months was 95F (35C), according to the data from the National Weather Service. The average daily temperatures for these months ranged from 104F (40C) to 85F (29C), while for
some days daily highs reached 115F (46C). For areas that see these average temperatures DEF shelf life would be 6 months.