A few years ago I was detained by Canadian customs officials (no handcuffs but not free to go) trying to enter Canada in my Bluetec.The Bluetec,unlike my BMWs,didn't have "free" maintenence and it was starting to show the "1000 miles until no start" warnings so I brought a 2.5 gallon jug of DEF and an adapter nozzle.The officials asked me several questions about the fluid,took the jug into their office and after a half hour they declared that I was free to go *without* the jug.Luckily I was able to get through Canada on what I had left in the car.
Kinda curious...and a bit annoying because I thought there were at least a few diesels sold in Canada that required DEF.
Live and learn I guess.