So, are you running singles or duals? In any case, make certain that whatever you run will clear your brake drums.
Tire selection is greater in 16" sizes. If you are concerned about overall height, there are 16" tires that are as tall as 19.5" tires; I have some 16" NDTs that are taller than most of my 19.5" road tires.
Something else to keep in mind is that wheel/tire changes are likely to affect your unsprung weight (mass) which in turn will affect the driving characteristics of your truck.
Good luck.
Last edited by 1956; 06/28/2008 11:49 PM.