car accelerates very slowly
 

2003 g35 coupe 5at

I changed my radiator because the old one was crack. I start my car and go to take off and it barely wants to move. The engine revs all the way up just fine but it feels as if im driving a manual car and im just barely releasing the clutch. What's going on?

Edit: Transmission fluid was spraying from tube going to radiator. New tube and fluid.