supposable it expires. And I don’t truly understand how or why. It’s water and fertilizer. As to is it better to run the tank low or put a jug in as needed, I have no clue. I’ve done both and probably don’t drive enough to see difference.Can the DEF in your tank expire?
I was planning on letting my tank get a little below half a tank and then just topping it off with a new 2.5 gallon jug.
Would that be a bad idea?
Since heat is it’s enemy, I’m assuming that DEF in the tank, especially in AZ-like climates, goes bad quicker than the jugs stored in A/C. I only drive 6K miles per year - that's about a tanks-worth, but it's living at well over 100° for a substantial portion of the year.Can the DEF in your tank expire?
I was planning on letting my tank get a little below half a tank and then just topping it off with a new 2.5 gallon jug.
Would that be a bad idea?
You've never tried to design something that the marketing department is in charge of, have you?If there was a legitimate concern the engineers would have put it in the manual. That doesn’t mean engineers are infallible, but they right 99% of the time.
Diesel Exhaust Fluid doesn’t degrade nearly as quickly as people assume. For example, at 86°F, DEF has a shelf life of a year. REMEMBER: Do not equate shelf life to spoiling like food, as DEF will not go bad. It will lose some effectiveness, and the SCR will dose at a higher rate, but it won’t “go bad.” If maintained at a constant temperature, DEF manages to stay for several months. For example, at 74°F in Los Angeles, Diesel Exhaust Fluid has the shelf life of 44 months.