
Was this his first time in the car ?
We initially used to sit our pup on our knee so he would be calmer and we could reassure him should he get upset . Luckily he has always been fine in the car .
You could try introducing him for a couple of minutes , just sitting in the car with him without actually moving and give him a treat while he is there so that he gradually comes to associate it with nice things . You can do this at anytime without actually going anywhere .
Another way to drive him is in a crate that is covered as some dogs get a little unnerved when mobile by the motion of the car etc.
Given time he should come to accept it
Lel