I have a 2006 Dodge 2500 4X4 Quad Cab with Cummins and automatic transmission. The truck had 10,000 miles on it now and for as long as I can remember when the truck is cold and you put it into drive you really have to rev up the engine to get it to move. After about 5 seconds of warming up no more slip. I spoke to the dealer and they said it was normal. Any thoughts? Also, I usually put it into drive now and wait a couple of seconds before taking off. No slip that way. I checked the fluid level and it is full. Thanks for any help.