Loud "Thunk" - 4Runner and Hensley Cub

[SteveSueMac]

Originally Posted by philipsinewe

This is not the Hensley Bump. Totally different situation.

Can you say more? What do you think it is? Thanks.

[philipsinewe]

The bump is from the trailer moving forward as you are breaking, in a turn. In that situation, the trailer hitch has "play" and if your trailer brakes are not set properly, the trailer thumps forward. It, in part happens on all trailers, in that the trailer is pushing forward. Thus trailer brakes are important to be set aggressive on all trailers. With the Hensley you also get that thump. You clearly need to be aware of it.

What this original thread is referring to is the hitch bar "popping" in the receiver box at low speed. No big deal at all. I find all the "fixes" kind of silly, for me, it reminds me that I have a very nice hitch, and that I have 10,000 pounds that's wants to sit in the passenger seat with me. But to each his own.

[rmkrum]

That explains why I set my Prodigy II controller to boost 1 or boost 2 depending upon terrain. That pretty much eliminates bumps from weak trailer braking. Much more aggressive braking curve this way.


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[BandL]

So I emailed Hensley about the use of rattle reducers, and here is their response:

Byron,

We don't have a specific recommendation on using such a tightener. Usually
any noise created in the receiver can be mitigated by spraying silicone
spray inside the receiver so it will move a little easier without creating
noise.

Any sound created in the vehicle receiver will not alter the function or
performance of the Hensley Hitch so its up to you if you decide to tighten
it up.

Having ruled out everything else, and seeing how common the 'rattle' is, I am comfortable that this is what I, as a newbie to towing, am experiencing. I like the lubricant idea is general, so will start with that and then perhaps add a specific device.

Thanks to all - I learned something.

[m.hony]

The $22.95 anti-rattle device certainly cannot hurt anything.
Without it, the shank will wiggle around and start to distort/elongate the pin hole.
With it, no worries.
Seems like you would still get the "Hensley bump" braking, backing, or staring from a standing stop due to the design of the hitch.


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[dznf0g]

Originally Posted by m.hony

The $22.95 anti-rattle device certainly cannot hurt anything.
Without it, the shank will wiggle around and start to distort/elongate the pin hole.
With it, no worries.
Seems like you would still get the "Hensley bump" braking, backing, or staring from a standing stop due to the design of the hitch.


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If you're talking about the stinger moving around and clunking in the receiver due to not much WD "binding" it in place, I agree......but that's not the "bump".

It takes a pretty hard braking event, in a (minimum) slight turn to get the bump. It is caused by "over-rotation" by the swing arms, for lack of a better term. Tight bearings (all 8 of them) will help minimize it dramatically. I've only experienced it 3 times, all during hard braking and some steering input to head for an escape route, if needed. Struts need to be adjusted for centering of the head and box and need to be pretty firmly under compression.

[Barneys]

Try a Hitch-Vise. http://hitchrider.com/nowobble.htm
I have one that I use on my bike carrier and it really stops all movement of the shank in the receiver.
Barney