Add unit to these..

[Jas.per]

The Car

and

how to add units on that car???

 

[ap0calypse]

It's probably done with attachment.

Certain models have different attachment points, could be that this one has 6 extra attachment points where the units are.
Then you can create a special effect with the model of a soldier on those attachment points and done: it will look as if the soldiers are inside the car.

Since I have don't have that model to check this, I cannot be sure, but it seems logical to me
Might also be done with triggers (just some units that follow the position of a car), based on this screenshot it's kind-of hard to tell.

 

[defskull]

Don't tell me it's a custom model with the custom animation.

 

[Rozll0rt]

its a model car with soldier and a car with an attachement villager, the villager is just an attachment

 

[darkzxx]

so basically just attach that model to a ship or a transport car in warcraft 3 and use trigger

Event : A unit is loaded into transport

condition : Transporting unit = the car

Action = Create a special effect at the car with the unit