Did You Lube the Ball?
All hitches (Except perhaps the Hensley Arrow) want a couple drops of "On-the-Ball" hitch lube each time you hitch up. Don't over lubricate. Clean the dirt and grime off the ball with a rag or paper towel before you apply the lube.
Reese advises no lubrication at all on the cams of the dual-cam sway control hitch, but like dwightdi advises you may find a lube that eliminates the noise but won't compromise the hitch design. I found a heavy drill-bit wax worked well.
Back to the hitch ball itself, "On-the-Ball" by Reese comes in its own plastic-applicator bottle. A bottle will last for years for most of us.
Equalizer Brand hitches want lube on the hitch ball, where the bars rest in their brackets, and where the bar sockets meet the hitch assembly.
Each hitch set up has different lubrication requirements that you haven't complied with yet. There is no break-in period. What you are hearing are the protestations of an un lubricated hitch.
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