Bang sound when towing travel trailer

[robinaronson]

We are towing a 30-ft travel trailer and it has just started making an occasional 'bang' sound when towing. It doesn't seem to be associated with hitting bumps (which have a different sound - 'ba-doomp ba-doomp'). It seems to always happen when we are driving in a straight line on a fairly smooth road, and usually between around 40 - 55mph. Less on the interstate than on other roads. We have been towing the camper for almost 2 years - almost 40K miles, and this 'bang' sound is new. It happens only occasionally, and we can't seem to make it happen at any particular time. It just started within the past few weeks, after the camper sat for 6 weeks without being towed. I feel like it is somehow associated with the hitch, but that's just a guess. Any insight would be greatly appreciated. Thanks!
Robin
2007 Palomino Puma Travel Trailer 30-ft 6800 lbs
3500 Chevy Van, Husky Equalizer Hitch

[baraff]

Robin - does this happen when accelerating or decelerating? When we had our TT sometimes the hitch would slide in the receiver, just a 1/4 inch or so, but enough to cause a good size clunk. I would make sure your hitch pin is the proper diameter for the hole, be sure you're not using a 1/2" pin in a 5/8" hole for example.
Also, do you grease the hitch ball and weight distribution bars before each use? I used to smear a small amount of wheel bearing grease on the ball and bar socket ends to prevent binding. (And wear)
Hope this helps.

[baraff]

Also, do you use a sway control system? If it is cranked down too tight it might be binding on turns or when the TT starts to sway. Try backing that off a 1/4-1/2 turn and see if that helps.

[robinaronson]

Thanks - we're using a Husky weight/distribution / sway control system (heavy duty) that we've had for about a year now. We're not using the extra sway control bar that some people use. Since this bang is new, maybe it does just need to be greased. We'll try it. Thanks!

[jhamihvfd21]

I would check bolts on the hitch and maybe spray some lube like white lithium grease on the trailer suspension components because they could be sticking

[CD]

I would get under the TT and look for anything that doesn't look right like cracks, breaks. bends etc. Check frames, axles, springs and hitch including on the TV up to where it is bolted to the frame.