wont start is dumped in gear

if I dump my truck when its still in gear then put it in park, when I try to start it again later it just clicks like the battery is low. I have to push it forward a couple inches then it works. I make sure its in park and its fine, Im just curius of why.

sounds like a starter problem..like its not catching or is off or something..my old yota did that...put a new started in and bam..worked fine all the time

my friends taco did that and he ran a new wire from the ignition to the starter and never had a problem since