2002 Kia Sedona cold starting moving automatic stick to rev

i need to let the car warm up for at least 4 minutes before i can move the stick shift on my automatic transmission through the gears from reverse to drive i cannot do this when first starting the car the stick will not move so i have to let it warm up and come back 4-8 minutes later before i can move the shifter through the gears does the shifter need to be lubed or something so it does'nt stick or is this something bigger i have the 10yr 100,000 power tran warrenty
do i need to let the dealer see this or is it something minor that i can bring it to the local AMCO and have them look at it and correct it for a resonable fee any help apprecatied thanks