There's a form that you can fill out on the DMV website that you can gift someone a car. I would assume you would have to have it registered to your brother.
You'll need your grandfather's current registration and title if your have it. Probably a copy of his death certificate.
Even though the truck isn't running he'll most likely have to register and insure it, not to drive it but just to make it legally his in the states view. He should do this asap especially if his or his heirs intention is to ever fix it or sell it. Even junking it will be easier if it's legally his in the eyes of the state and that's best accomplished with a registration.
Sorry about your loss.
Recently just went through this. Called the DMV and the woman there was very nice and sent over all the documents we needed to fill out and gave us a list of what we'd need to bring. She even set up the appointment for us.
Maleficent_Weird8613 t1_j63avez wrote
There's a form that you can fill out on the DMV website that you can gift someone a car. I would assume you would have to have it registered to your brother.