Ans. No, you can not install a double din head unit in every vehicle. To pick the right double din head unit for your car, you have to make sure the dimensions are correct and pick the right options for your car on that basis. While the dimensions of the double dins present in cars are usually the same, if you are looking to install one in a truck or some other vehicle, you have to consult it with the seller and ask if the unit supports your vehicle or not.