Question: Where has the truck been for 5 years? how was it registered? How was it plated and driven. If you are looking to buy it from your dad so you can use it here in Texas, it may be more trouble than it is worth.
You either need to probate your grandfather's estate under intestate laws, to have letters testamentary issued which will allow someone to sign and transfer the title from your grandfather's estate to whomever. But that is likely going to cost more than the vehicle is worth. (at least $2,500) So only go this route only if there is other property still in your grandfather's name that needs to be title transferred. (Houses, land, cars, boats, etc.) Otherwise, I recommend you consider a bonded title. Your last option is to forget about title and sell it as scrap, or walk away from the vehicle.
This is why you need to take care of business. People avoid doing the correct thing (probating grandpa's estate) then the have tons of little issues down the road.
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