Clunking noise while towing

I am using a 15k Reese hitch with kwik sliders

I had one of those and clunking.

1. When you are starting and stopping, have someone look at the handle and see if there is any movement.

2, Check all bolts for torque, on both hitch and underbed.

3. Make sure handle is in locked towing position.

There is some inherent movement in the hitch. You may not be able to see or feel it when pushing by hand but 1500 lbs of pin weight is another story.

I had clunking or something of the sort on another trailer. Turns out the wheel bearing nut was not tightened properly and the wheel was making the sound when stopping or starting.