I'm iffy about the truck, but it's totally possible for the guy to survive the bullets.
As mentioned by previous posters, a person's body is basically (in the purposes we're talking about) stopped by 3 things - central nervous system disruption (if your brain isn't connected to anything through the spinal cord, you can't move anything voluntarily), lack of oxygenation (loss of perfusion, blood loss etc., - if no oxygen gets to the brain, the brain can't voluntarily control what's going on, organs and muscles shut down, etc.), and a mental perception of what is happening to the body (what some of you call shock, also called acute stress reaction - the mind responds to terrifying stimuli and basically starts shutting things down).
Let's talk about the 3rd example, the acute stress reaction. Your body has a bunch of neurotransmitters and stuff. The ones that are pretty much responsible for this acetylcholine on pre-ganglionic receptors that end up releasing things like adrenaline (epinephrine), nor-epinephrine, and other catecholamines. PCP can decrease these effects on the pre-synaptic neurons in some parts of the brain, and increase them in others. So you can get increased blood pressure, increased heart rate, etc., without a person actually having actually having "shock". PCP also works on other receptors (dopamine, NMDA, etc.) which ends up leading to several things like amnesia, analgesia, and disassociation of the body and mind (which prevents the body from freaking out and shutting down!). We use a related drug called Ketamine in the ER sometimes to put people out if we have to intubate them. After speaking to some of these patients, they tell me that they felt like they were another person in the room, or flying over their body.
If it all seems very confusing, it's because it is! Psyche medications are very complicated, the receptors and neurotransmitters are all related and can all have different type of effects depending on where they're located, how they're activated, if they're inhibited, etc.
Anyways, I kinda got distracted and forgot what my point was. Basically...a person on drugs is still stoppable. Just remember, that 3rd way of stopping them probably isn't going to work (what most people call "shock). Because of the catecholamines (things like adrenaline/epi) going around in their body, the lack of perfusion route (a different form of shock) won't be your best bet either (although it will still work eventually, the body just runs out of oxygen and shuts down). CNS disruption will always stop a person the quickest.
If you have anymore questions or I kinda confused you or made things seem really complicated...it's because when it comes to psyche meds, they are! I am no expert on them but I did have a lot of schooling on them so I hope I cleared some things up and helped out some! Let me know if you have any more questions, and I'll try to answer them to the best of my ability.
~Doctor of Pharmacy