A vehicle takedown is done by shooting at, and destroying, other vehicles whilst driving one yourself.
Toggling
button whilst driving will bring up your aim reticule. With high aim assist, the reticule will automatically target parts of enemy vehicles, such as tires, gas tanks, etc.. you can switch between them by tapping
. Your targeted area is also described in the bottom right of the screen.
I’ve found the best way to do this is to approach the enemy vehicle from behind (The drug dealing taxis are great candidates), aim at the fuel tank at the rear, and let off seven or eight quick rounds. The tank catches fire and explodes before any of the occupants can get out.
For those of you have have finished the game and want to mop this up, this can be done with police cars too.