My son has an 85 Dodge Ram truck with lots of miles on it. He had tons of play and found that the coupler was the culprit. He bought a kit to replace the parts and when he took the old parts out he could see the wear. The new parts fixed the issue. If/when you replace the parts, be sure to pack it with good grease and be sure that end piece fits snugly. The picture you showed has it hanging off.
