Hello all, new owner here. Just purchased a 2017 XD Diesel. I'll be snooping around to see what upgrades i can do. It does have a DEF delete, but i have yet to figure out what the different settings on the switch are for. I attached a picture if anyone can help me out with that, it would be greatly appreciated. Next step, find a train horn. My wife has to have the train horn like or previous Titan. A lot of people don't understand what the left lane is for and how to use a turn signal, so she reminds them. This is my first Diesel outside of the Military so i've got to do some research and figure everything out. Looking forward to learning what can be done for ascetics and performance.