Is it legal to carry a loaded firearm in a commercial vehicle?
 

Provided you have a carry permit, you're in your home state or you're in a state that honors carry permits from your home state, can you legally carry a loaded pistol in a CMV?

Contrary to popular belief there is no Federal law against it nor is there any FMCSA rule prohibiting it. But most carriers and shippers don't allow them on their property. Some states like NY don't honor any other states permit and NYC doesn't even honor a NY state permit! Do you ever drive thru NY or the DC area? How about NJ and CT. don't get caught in any of them without that states permit. In DC you will get arrested for just having ammunition!
Be careful and don't tell ANYONE!

Yes, you can but make sure you know where you'll be going. Will you possibly cross a state line that doesn't accept your permit? Could you be dispatched to something on Gov't property of some sort? Plus the bigger issue in many cases is how your states laws are set up for carrying firearms. In my state my company can have any policy they want, I can sign no firearms policies all day long and in the end it means nothing. The worst that my company can do is fire me. That's NOT the case in all states, in some, you can be charged for that. There's a lot you gotta think about ahead of time. I see your in GA which I know signs don't have force of law (remember the Federal ones still do!) but you still gotta consider everything.

With all the alternatives to firearms, why not carry one of these.
A pepper spray pistol, not the little finger pushers, but a full size canister pistol that shoots 30 feet, a good quality stun gun, not the one you have to be up close and personal, but one that looks like a gun and shoots the wires with the barbs.
I used my pepper spray at a Baltimore Walmart last October, and you don't ever have to be accurate. The two guys came around my trailer and I simply pointed and sprayed, no warning no nothing, they never saw it coming, they were down and done for 20 minutes after the police arrived. The beauty part, I got into no trouble at all. No permit, no death, no nothing.
I've carried this in my truck for 10 years and finally had to use it.

In many places Mace/tear gas and even pepper spray are considered illegal to have same with stun guns!

You could get a can of wasp spray rather than pepper spray. It has a longer range and is not illegal in any state, as far as I know. Shoot someone in the eyes with wasp spray and they will leave you alone. Rather than getting a stun gun or pepper spray, I would rather take my chances with a firearm, if I were concerned about personal safety. It can be a problem on some military bases as well as other properties. I picked up on a military installation a few weeks ago. At one time they would allow you to check your weapons prior to getting to their gate. That is no longer the case. They won't allow any firearms on the base, nor will they allow you to check them. I don't know if this is the case at all military bases, but this particular facility used to be more friendly toward firearms. It could be something with the current administration rather than bases in general. If you enter Canada, you don't want to get to the border with a firearm in the truck. It could be a quick trip to the prison and your equipment could be impounded. It would be best to familiarize yourself with laws of those states in which you travel. Each state is different.

Yeah, but if they catch you with it its only a ticket, you won't be going to jail for carrying an unlicensed firearm, I'll take my chances with the pepper spray. It's not an issue in Maryland,...probably why I got into no trouble at all.

I just can't go the wasp spray route, the legal liabilities of spraying a person in the face with actual poison are nothing I want to mess with. Criminals already have enough rights, they don't have the right to sue me for spraying them with a possible poison.

As far as military bases, I used to be able to check my weapons (pepper spray, stun gun, machete) but like you said, some won't now, and as far as I'm concerned they are not firearms so I don't even bother mentioing them, I just stow them where they will never find them during a compartment inspection. I also carry propane tanks and some are ok with them , and some bases lose their minds when they see the tanks. So I have to remove them and pick them up on the way out.

The simple answer is NO. The question was "can you transport a LOADED weapon in a cmv" with RARE rare exception can you carry a loaded firearm be it on your person, car, motorcycle, or cmv. In your home state (or reciprocate states) can you transport a loaded firearm with a Concealed Carry Permit. This goes for all states in this union, even open carry states have distinct limitations and exemptions within the states. If you wish to carry a firearm keep it unloaded and separated from your ammo at which point you may want to consider alternatives mentioned here.