Just a note, just because it seems to handle ok, doesn't mean it's safe or legal. If you can't do it just fine driving with it without air bags, you cannot do it. Air bags are not there to increase your load capacity, they are simply there to keep your truck level. A stock half ton I would consider it with light sleds. Lift or 4 strokes NEVER, your asking for problems. My 1 ton with 6" lift and 37" tires with a deck and two sleds you could feel it pretty good, and the wind was felt in the steering.
I can tell you right now a lifted half ton with 2 sleds you won't get very far in B.C without being pulled over, and told to leave one sled. Because it is overloaded for sure, the lift and tires add a good 300+lbs, and a half ton is REALLY pushing it as is. And the fact that it looks and is unsafe. Doesn't matter if you got air bags, the rear axle is overloaded, and pushing the brakes.
Yes you do need 3 clearance lights across the back and 1 orange front 1 red rear, don't need cab lights here, but might some places, overall width varies but 102" most places.
I really feel it is a good thing they are cracking down on it, way to many unsafe loads on the road, whether it's sleds, quads, or travel trailers. Because people with a half ton, get a deck and two sleds and say o well it handles ok, lets pull a 2 place, and have 4 guys in the cab, and overload the truck to hell, and are a huge risk to everyone else on the road.
I wouldn't do it, I can tell you right now next year will be worse yet, heard of some guys with 2500's being weighted in and overloaded, with just a deck and 2 sleds NO trailer. DOT isn't stupid, they can spot a half ton a mile away without looking at decals, and KNOW what things weight, and even if your close and still "legal" they can still tell you you aren't driving with it.