CougarnewbieExplorerDec 08, 2020Stale DEFBecause of Covid my F-350 6.7 diesel has been garage kept since February. The DEF tank is full. DEF has a shelf life. Should I be concerned enough to consider draining the old DEF? My first diesel. T...Show More
rhagfoExplorer IIIDec 08, 2020Well why didn’t you do some day trip driving with it during the summer months?