General:
* Taxi
* Hackney
* Carriage
* Automobile
More specific:
* For a taxi: Yellow cab, black cab, ride-hailing service (like Uber or Lyft)
* For a truck: Truck cab, driver's cab
* For a train: Locomotive cab, engineer's cab
* For a boat: Captain's cabin, wheelhouse
Informal:
* Ride
* Wheels
The best synonym will depend on the specific situation and the level of formality you need.