I know a few guys up here that have had Dodge trucks go into limp mode almost 700 miles north of Fairbanks (closest dealer) and go no faster than 5 mph thanks to DEF freezing.
At this point, I'd rather put a ton of money into the 05 than worry about DEF.
I haven't heard of issues with the Chevy or Ford DEF systems.
05 2500HD CC LB LLY, 4x4, 3.73s 235/85R16's, webasto cab heater, to keep it warm.
03 Buick Rendezvous - When you average over 80 miles per day driving around, you need one of these.
85 K-5, 6.2, SM465, Rockwell T221, 1 tons, 36's. More goodies to be installed as time and money allows.
82 K20, 6.2, SM465, NP208, stock except for bed rack, snow plow, and glow plugs are on a toggle switch. It works great for plowing!
72 Postal Jeep - Yet another project