Okay y'all I have a 96 f350 srw 4by4 7.3 powerstroke fully built , she will go into reverse but when you put it in drive it's like being in neutral it's an automatic 4 speed transmission can anyone help do I need to rebuild or just get a new one any input will help

Caveman Diesel's LTB

 

What happens if you manually put it in 1st

 

Welcome to FTE.
What's fully built the engine or the tranny?

 

Motor is built trans is not and the o/d light starts flashing

 

OD light flashing means a code has been set. The e40ddoesnt need any electronics to go into 1st or R I'd say you are in the need of a rebuild