DEF Shelf Life!
Just a quick tip for those that are new to Diesels with all of the newer emission controls. DEF apparently has a shelf life and using anything other than DEF bought from the dealer may void your warr...
Forum Discussion
There is nothing in the manual that I recall about buying DEF from the dealer. So I think you were being lied to. As someone who used to buy 50% Urea (DEF is 30% Urea) by the truck load several times a week, I can say that the hotter you keep your DEF - the faster it will break down to ammonia. If you open a bottle and a sniff takes your breath away and makes your eyes water for 5 minutes, then that bottle is degrading to ammonia. But that is what happens in the truck so ammonia won't hurt the truck it may just make the DEF a little less effective.
