I start out and every thing works fine when tranny is cold. Will drive around and work the truck like normal. After the trany gets up to temp range, I will put it into park get out (with out turning if off) and say look to see how further I need to back up to my trailer. I get back in put it in to drive or reverse it does not move. I give it a little throttle it will jump witch ever way it is in. I tryed a search but could not seem to fine the problem. Does anyone have an idea on this?
Thanks,
ricefarm

When was the last time you serviced the transmission? If it's been awhile I would start by changing the spin-on filter and fluid.

Just the fluid that comes out when I take the filter off, or all of the fluid? And if all fluid that is how many quarts?
Thanks,
ricefarm