Class 4 Trailer Hitch Ball
Choosing a class 4 trailer hitch ball means matching the ball to the load path between the receiver, drawbar, coupler and trailer frame. The rating of the hitch itself does not override the individual limits set by the ball, ball mount, coupler, axle rating, gross vehicle weight rating, combined weight rating and the payload the tow vehicle can support. A heavier class 4 receiver can accept a high-capacity ball, but the setup is only as capable as the component with the lowest approved figure. The right choice therefore depends on configuration, shank diameter, ball diameter, tongue weight and the actual trailer being pulled.
The direct answer
A class 4 trailer hitch ball is not a single fixed product rating. The class describes the receiver's structural category before a ball mount and ball are added, so the ball must be selected separately for the shank diameter that fits the drawbar hole and for the gross trailer weight being towed. Most class 4 receivers are matched with a 1-inch or 1-1/4-inch shank ball, but the final load capacity comes from the ball's stamped rating, not from the hitch class alone.
The immediate check is to read the ball's markings, including diameter and the maximum gross trailer weight and tongue weight it is approved to carry. The ball must also match the trailer coupler size, commonly 2 inches or 2-5/16 inches. A coupler that is slightly loose on the ball creates impact loads that exceed the rated tongue weight, so diameter and clamping condition matter as much as the class 4 label on the receiver.