Disconnected Wires hanging down at the rear differential on straight truck

Well I just took the bare wires and hooked up some jumper cables to them to see what happened but I couldn't get it to do anything. It didn't make any noise at all

 

I checked the connector and juice is running through it

 

I tested it out and either the circuit or the motor is shot. But then I manually selected the other gear and it is actually the smaller/shorter gear so I don't think this will be very beneficial to the high rpm highway speeds. What gears would be good for an eaton 10 speed to maintain lower rpms when cruising down the freeway? Like I said previously, I am #### near at 3,000 rpms to hold a 70-75mph speed.