Originally Posted by Sled dog hotel

Depending on what car you have, have you got a dog guard (assuming you havent got a big enough car for a dog crate his size) sometimes that helps if use a dog guard and a car harness and put them on a short tether lead. Also as he is a sight hound sometimes it helps if you block off some of the view with the mesh type sun blinds, also as someone has also said DAP products do tend to calm them. You can get the sprays and also the collars, worth a try.

If he gets hyped up as soon as you get the lead out, its usually because of association lead means walks so he starts to get hyper in anticipation. You could try desensitising to it, by just getting the lead out but then just sitting down. so he learns that the lead doesnt necessarily mean going out. once and if this is successful you could teach sit to wait for the lead to be put on with a treat at first if necessary. Once this seems ok, then teach sit and wait at the door, until finally opening the door, if he goes to bolt out then bring him back close the door and repeat it, until his trained that bolting out hyped up doesnt get him out. Final step is wait while you step out then tell him to come. With training him to be calm and wait for instructions that should mean that your in control and his not hyped up even before you start.

Next thing is that is sucessful is to sit and wait at the car, then sit and wait with the door open until he is told to get in. I would then teach the same with the car stationery as an exercise, then move to with the engine running and if you can maintain control then finally on a short journey, maybe even just bringing him back and not actually going to the park for a few times, that way he should hopefully realise and stop the hyper anticipation and over excitement that at the moment happens because car always means walks and a free run.

Not a quick fix by any means and will have to probably be taught in stages but an idea that might be worth trying.