* Accidentally causing a serious accident: Missing parts will severely impact the truck's handling, braking, and overall safety. You could lose control, leading to injury or death for yourself and others.
* Getting pulled over and ticketed: Police will likely notice the missing parts and pull you over. You could face fines, and possibly more serious charges depending on the severity of the missing parts and the resulting danger.
* Vehicle impoundment: The truck may be impounded until the missing parts are replaced and it passes inspection.
* Insurance issues: Your insurance company may refuse to cover any damages or injuries resulting from the accident caused by the missing parts. They might even void your policy.
If you're driving a truck that is *itself* missing (meaning it was stolen), then you're committing a crime: Grand theft auto. The penalties for this are severe and can include jail time, significant fines, and a criminal record.