Getting a unit to adjust it's pitch on terrain

[darwin]

I am making a car game. Some units in the game that are car like will tilt up and down when driving on hills (like Hellion, Orion Turbo Coup). Other units will not tilt at all, and whether going up or down hills they look like they're driving on flat ground (Dump Truck, Cargo Truck, and Shikoto Coupe). I want to make those units adjust their pitch like the first units do.

I attached a Dump Truck to one of the cars that worked appropriately, and the attached model does move up and down the hills appropriately, but I don't want to have to attach models to dummy units if I don't have to.

I tried the trigger line: "Unit - Turn Cars[CV1].Unit Ignore Terrain Height state Off" but it didn't work.

Is there something in the Data Editor that I can change that will fix this?


UPDATE:

I duplicated one of the units that actually works correctly and adjusts themselves to terrain. I duplicated the actor and the model. I then went to the model (not the actor) and changed it's basic model to the model of the car that won't adjust for terrain (the coup). This looked like it worked in the editor - when I put it on a hill in the editor it would be on it's side. But when I played the game it was still flat while going up and down hills.

Anyone know anything else I could try?