Sorry for resurrecting an old thread but just had this come up on my 2020 with ~17k miles on it. This is my first diesel so this may be a dumb question but is it normal for a truck less than two years old and this amount of mileage to need a coolant top off? It does not appear to be leaking. I don't smell anything funny, no signs inside the engine bay, nothing on the driveway when parked, etc.
Just want to make sure I don't need to take it into the dealership. I did have the HPF pump replaced a few months ago...would they have needed to unhook some coolant lines to gain access to the pump?