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?
"Storing DEF in a cool, dry, well-ventilated place is recommended to maximize shelf life. It will degrade over time, but if stored at temps between 10 degrees and 90 degrees, DEF has an expected shelf life of one year. You can extend the shelf life to two years by storing at a temperature that stays around 75 degrees."