Hey cctrucker, the law does not specify what kind of vehicle. It only says motor vehicle. That means that a big rig is a motor vehicle and you can keep and carry your weapon in it. That being said you have to take a couple of things into consideration. Is the big rig you are driving yours or does it belong to the company you work for? Also the law does not say you can not have a gun in your vehicle in a government owned parking lot. But the federal government and especially the military can keep you from carrying on their property. While the law does say that no public or private employer shall prohibit a visitor from having a legally owned gun locked in their vehicle in the parking lot, I may not want to test that premise. So if the rig belongs to your employer, then your employer has the right to prohibit you from carrying in their vehicle. While the law does not especify the kind of vehicle it does say "within their motor vehicle".
Here is the Statute
790.251 Protection of the right to keep and bear arms in motor vehicles for self-defense and other lawful purposes; prohibited acts; duty of public and private employers; immunity from liability; enforcement.--
(1) SHORT TITLE.--This section may be cited as the "Preservation and Protection of the Right to Keep and Bear Arms in Motor Vehicles Act of 2008."
(2) DEFINITIONS.--As used in this section, the term:
(a) "Parking lot" means any property that is used for parking motor vehicles and is available to customers, employees, or invitees for temporary or long-term parking or storage of motor vehicles.
(b) "Motor vehicle" means any automobile, truck, minivan, sports utility vehicle, motor home, recreational vehicle, motorcycle, motor scooter, or any other vehicle operated on the roads of this state and required to be registered under state law.
(c) "Employee" means any person who possesses a valid license issued pursuant to s. 790.06 and:
1. Works for salary, wages, or other remuneration;
2. Is an independent contractor; or
3. Is a volunteer, intern, or other similar individual for an employer.
(d) "Employer" means any business that is a sole proprietorship, partnership, corporation, limited liability company, professional association, cooperative, joint venture, trust, firm, institution, or association, or public sector entity, that has employees.
(e) "Invitee" means any business invitee, including a customer or visitor, who is lawfully on the premises of a public or private employer.
As used in this section, the term "firearm" includes ammunition and accoutrements attendant to the lawful possession and use of a firearm.
(3) LEGISLATIVE INTENT; FINDINGS.--This act is intended to codify the long-standing legislative policy of the state that individual citizens have a constitutional right to keep and bear arms, that they have a constitutional right to possess and keep legally owned firearms within their motor vehicles for self-defense and other lawful purposes, and that these rights are not abrogated by virtue of a citizen becoming a customer, employee, or invitee of a business entity. It is the finding of the Legislature that a citizen's lawful possession, transportation, and secure keeping of firearms and ammunition within his or her motor vehicle is essential to the exercise of the fundamental constitutional right to keep and bear arms and the constitutional right of self-defense. The Legislature finds that protecting and preserving these rights is essential to the exercise of freedom and individual responsibility. The Legislature further finds that no citizen can or should be required to waive or abrogate his or her right to possess and securely keep firearms and ammunition locked within his or her motor vehicle by virtue of becoming a customer, employee, or invitee of any employer or business establishment within the state, unless specifically required by state or federal law.
(4) PROHIBITED ACTS.--No public or private employer may violate the constitutional rights of any customer, employee, or invitee as provided in paragraphs (a)-(e):
(a) No public or private employer may prohibit any customer, employee, or invitee from possessing any legally owned firearm when such firearm is lawfully possessed and locked inside or locked to a private motor vehicle in a parking lot and when the customer, employee, or invitee is lawfully in such area.
(b) No public or private employer may violate the privacy rights of a customer, employee, or invitee by verbal or written inquiry regarding the presence of a firearm inside or locked to a private motor vehicle in a parking lot or by an actual search of a private motor vehicle in a parking lot to ascertain the presence of a firearm within the vehicle. Further, no public or private employer may take any action against a customer, employee, or invitee based upon verbal or written statements of any party concerning possession of a firearm stored inside a private motor vehicle in a parking lot for lawful purposes. A search of a private motor vehicle in the parking lot of a public or private employer to ascertain the presence of a firearm within the vehicle may only be conducted by on-duty law enforcement personnel, based upon due process and must comply with constitutional protections.
(c) No public or private employer shall condition employment upon either:
1. The fact that an employee or prospective employee holds or does not hold a license issued pursuant to s. 790.06; or
2. Any agreement by an employee or a prospective employee that prohibits an employee from keeping a legal firearm locked inside or locked to a private motor vehicle in a parking lot when such firearm is kept for lawful purposes.
(d) No public or private employer shall prohibit or attempt to prevent any customer, employee, or invitee from entering the parking lot of the employer's place of business because the customer's, employee's, or invitee's private motor vehicle contains a legal firearm being carried for lawful purposes, that is out of sight within the customer's, employee's, or invitee's private motor vehicle.
(e) No public or private employer may terminate the employment of or otherwise discriminate against an employee, or expel a customer or invitee for exercising his or her constitutional right to keep and bear arms or for exercising the right of self-defense as long as a firearm is never exhibited on company property for any reason other than lawful defensive purposes.
This subsection applies to all public sector employers, including those already prohibited from regulating firearms under the provisions of s. 790.33.