It's a bit of a nebulous direction, but she can do that. She waits just long enough to watch his transformation (awesome), then applies the pedal directly to metal. The truck screeches forward and careens around a corner — not quite the right direction, but the most important thing here is getting out of direct line of sight from the scene of the crime.

She doesn't slow down until she's sure she made it away without anyone after her — and even then she's not going that much slower. This is still, after all, a stolen vehicle, and it'll be reported sooner or later. She glances out the window now and then, eyes skyward and looking for the robot up there, but mostly she concentrates on looking casual and normal. Just any old pickup, carting a load of propane around, nothing to see here!

Her looks upward get more frequent as she starts to draw away from LA proper, out further into the desert. If she doesn't get to see this guy again, man, she's gonna be pissed. She'd way rather have a second meeting with an alien than a shitty new truck.