HITCHBALLS

Hitchballs comes in three diameters:
*  1 7/8 inches (up to 2000 pounds; sometimes more)
*  2 inches (up to 6000 pounds)
*  2 5/16 inches (up to 10,000 pounds or more)

  Most importantly, be sure the ball is the proper diameter. A ball that is too small will cause the coupler to bounce loose. Some hitchballs have extended bases and shanks for special purposes. Such as a high-rise ball designed for use with some surge brake applications.

  The base and shank of a hitchball can have significant effects on its weight rating and some shanks may be slightly undersize or oversize. On step-bumper hitches especially, be sure the shank (in American measurements) conforms to the hole (which may be in an off-size metric equivalent, especially on some foreign trucks). If the hitchball fits too loosely in the hole of the hitch, no matter how tight you torque the nut, the ball will loosen rapidly and could come off. An insert is available from most hitch shops to compensate for this problem.

Torque recommendation: ( how tight the attaching nut should be) Usually, a hitch installer will just tighten it with as much strength as he can muster. But that procedure won't always ensure proper longevity of all parts of the hitchball. To install properly, first check the ball for the proper fit into the hole of the hitch, then, grease the threads and work the nut back and forth to cover completely.
Then, the general rule of thumb for torque, using a torque wrench is:

*   85 lb. ft. (Class I)
*  105 lb. ft. (Class II)
*  235 lb. ft. (Class III)
*  300 lb. ft. (Class IV)