When my truck sits for more than 5 hours, it starts up and idles extremely rough. Then when I put in reverse, I can hear the transmission spinning loud. When I put it in drive it clunks into first gear and as I go slams into second. After I go about a mile, I can turn off the car, restart and everything is fine. This issue started 2 years ago, lasted a week and went away. It then did it a year later for a few weeks and went away. It is back and just started to go away. The only time it does it now is if I have to stop short. It stops once I restart the truck. Any ideas?