my 1999 dodge ram 1500 4x4 when its idling it make a whining noise.

poss serp belt or related pulleys or tensioners is common

check your power steering fluid

If the whining is intermittent like it goes for a few seconds then stops for a few then goeas again it would probably be your AC compressor, mine does it to. Try turning the climate controls to off and wait a minute to see if it stops. If it doesnt stop it is probably your power steering fluid or pump itself. Or worse but probably not your torque converter.