Just bought a 2015 with half tank of DEF. Not sure how long it's been sitting on lot, at least a couple winter months. Should I top it off with fresh DEF or run this half tank out?
When I bought my ecodiesel the salesman told me not to fill it clear full till winter was over. It gets below zero f here in western pa. and the tank could freeze and split the tank. Bought it early February and filled it up in middle of March. That got me thru the next winter before I needed a refill.