I just towed a 26' enclosed trailer about 2,000 miles. The trailer weighed about 8,000 pounds loaded and 3,600 pounds empty. It was loaded for half of the trip and empty the other half. I always use an anti-rattle clamp on the ball mount when I tow.
rvthe.us
From the years of towing a 30' Airstream, I found the only way to keep the clamp from loosening was to go overkill and made a super strong clamp from two clamps I bought from Hitchclamp.com. The U-bolt that comes with this clamp will loosen in a few hundred miles, so I put two of them back to back with 5/8" grade 8 bolts. Each bolt, when torqued to spec, has a clamping force of 16,000 pounds.
When I got home and removed the clamp, I noticed the receiver pin was missing!!!! There are a few possibilities; 1) I never put the pin in 2) The pin somehow fell out 3) Someone stole the pin. I am 100% certain I put the pin in, so either it fell out or someone took it out. I have no idea how long the trailer was towed without the pin in the receiver and I am 100% certain that had the clamp not been on the receiver the ball mount would have pulled out. Obviously, if the ball mount would have pulled out, we would have at the very least had a mess. Count your lucky stars.
Why use an anti-rattle clamp? Which clamp to use?
While growing up on a farm, I probably towed thousands of times without any device to keep the hitch and receiver from moving around or "rattling". There really was no need. Towing was not much more than moving an implement or trailer a mile or two on a gravel road. Yeah, the hitch could be...

When I got home and removed the clamp, I noticed the receiver pin was missing!!!! There are a few possibilities; 1) I never put the pin in 2) The pin somehow fell out 3) Someone stole the pin. I am 100% certain I put the pin in, so either it fell out or someone took it out. I have no idea how long the trailer was towed without the pin in the receiver and I am 100% certain that had the clamp not been on the receiver the ball mount would have pulled out. Obviously, if the ball mount would have pulled out, we would have at the very least had a mess. Count your lucky stars.