Hyperactive, poor focus and excited!

Question
Me and my wife have a 1 year old GSD that we are having problems with. We also have a 1 1/2 year old Rottweiler but everything is going well with him.

The problem with the GSD is that he is always hyperactive, excited and with all of that he has a hard time focusing. While the Rottweiler can stay in a room and be calm and quiet the GSD goes nuts, cries and barks. When I go into the room he starts barking and crying and the same time he jumps on me like he wants attention - when I let them outside to the yard the GSD doesn't make a sound.

It takes a while for him to hear the "Sit" command but when he sits down he keeps crying and barking.

We bought a pickup "for the dogs" so they have enough space when we take a drive. The pickup has a covered platform where the dogs stay. The Rottweiler just looks out the window, really calm and quiet while the GSD barks all the way to the destination, sometimes the GSD barks for twenty minutes but then sometimes he calms down.

We got the GSD when he was 4 months old because he and his brother got PARVO. Some people say that the first weeks are the most important, that is week 8,9,10 and 11 but we missed that because of the PARVO.

The first four months of his live he just stayed with his other sick brother and my GSD was very dominant towards him, being the tough guy.

What is wrong and what can I do?

Answer
While better early socialization may have helped, it could be his breeding.  Neuter him if not already.  That should go a long ways toward calming him down.  You certainly don't want him passing on his ill behavior.  More exercise would help.  Long walks, fetch, time at a dog park, whatever you can do.