Pulling a 5th wheel RV trailer with a 1/2 ton.

Jadaharabi said
Your half ton Dodge pickup truck has a 9 1/4 rear axle. The axle bearings use the axle itself as the bearing race. I personally do not recommend that you pull a gooseneck or fifth wheel trailer using that rear axle.

This is true of a LOT of light trucks. GM did this "way back when." I'm not sure if Ford did or not