I'd double check to make sure ball and coupler are sized the same. If the ball is 1 7/8" and the coupler requires 2" there will
be clanking and banging.
Here's a little tutotorial about hitch balls.
If you have a wrench to remove the ball, the ball can be placed in a vice just snug enough to work it out and then measure the opening. You'll then know which size you possess. Some balls also have the size stamped on a flat spot on the top. Another noise producer may be a "stinger" with a hole larger than the bolt portion of the ball which can allow the ball to shift back and forth. Due to this problem, it's wise to take both stinger and ball if you've discovered the need for a replacement ball.
Many people are also unaware that different height balls are available to correct variations in level
height between tug and towed vehicle. Before purchasing a new ball, check the height of coupler on the trailer after it has been leveled and ball height on the tug when it is also sitting level. Corrections up to about 1" may be made with a different height replacement ball.
In review, hitch balls come in different diameters (to fit the hitch on the trailer), bolt diameters (to fit the hole in the bumper or "stinger"), bolt lengths (to fit different bumper or "stinger" thicknesses), and heights. All 4 need to be correct.
Hopefully these tips will help someone correct or avoid related problems.
& Ann K.