Rebuilt trans 6000 miles ago. This problem just started. I now have shift the selector from reverse to drive 4 to 5 times before trans will pull. The trans will pull great until I shut the truck off for about 10 min. then I have to repeat the above process to get the truck to pull again. The truck has 180,00 miles, 5.9 litre V8, 46RE trans. Any advice