wow... that's strange with your idle dilemma. i honestly have no idea... could be any of a handful of things. my guess is that it's somehow sensor related...since it only does it when the motor is warm. do you get a check engine light at all? if so, you can take it to someplace like pep boys and they can check the light for you, and see what it means. otherwise, once every 15 or 20 times probably doesn't warrant a very expensive trip to the dealer to have them diagnose it for you....
heh - unsullied beat me to it.
your truck sounds niiiice! for the first time in my life, i'm considering a truck. a beater 4x4, for my winter car... so i can store the z. my dad has always had trucks...and his latest GMC sierra rides like a cadillac. they've come a long way in terms of power and luxury!
the next thing i plan to get is an exhaust system...but that won't be until later in the summer at the earliest. things are pretty shaky here in detroit in terms of the job market...for everything. i'd better sock more money away in case a very rainy day comes....
report back if/when you figure out the stalling problem. i'm curious now.