Well, jd, the quick answer is "yes" you will most likely always be loosing transmission fluid; either from dripping-by various external gaskets and seals, or by passing-by the driveshaft/torque-tube bearing/bushing.
However, if your seals and bushings are good, the loss is minimal. Just check (and, top-up) the level of the transmission fluid every time you change oil (3,000 miles?), unless you see a lot of transmission fluid dripping under the truck (then, top-up more often).
Tim
