DEF how old is too old?
I have an opened jug of DEF dated July 2019. Can't tell if that is a manufactured date or an expiration date. Any ideas? Or should I just breakdown, dump it and buy a fresh jug?
Forum Discussion
- Having just bought my first diesel, I'm new to this DEF stuff and you got me wondering. Here's how to read the date code on Peak Blue DEF
Note that the year noted is the Expiration year, the year of manufacture is actually one year prior. So if your DEF is showing 2019, it was actually made in 2018 and is DEFinitely too old to use. :) - Dump it. Def has a shelf life. If it's stored in a cool place out of sun it's good for 12 months. If it's stored in direct sunlight then 3 months.
The key is in how it's stored. - I would question the age of the DEF that is already in the truck, perhaps the DEF in the jug is better.
- DEF's shelf life varies by temperature:
<50 deg, ~36 mo.
50-77 deg, ~18 mo.
78-86 deg, ~12 mo.
87-95 ~6 mo.
96-104 ~2 mo.
If you live in southern AZ probably should refill with limited amounts of DEF unless you drive a lot. Cummins12V98 wrote:
If stored in a cool place it’s most likely fine. Personally I would not use it. I on
only buy what I need.
Wow! took several responses before someone mentioned the most important thing....what was the temperature it was stored....that is the most important factor.Learjet wrote:
Cummins12V98 wrote:
If stored in a cool place it’s most likely fine. Personally I would not use it. I on
only buy what I need.
Wow! took several responses before someone mentioned the most important thing....what was the temperature it was stored....that is the most important factor.
Johnny, tell us what I won???!!!
