Thinking about Hensley Arrow hitch system

[KeithInSpace]

Those Nitto's are mean tires, as much "off-road" as I need to go onto my job sites. And they come in a great variety of rim sizes and section widths.

To clarify: I never get "sway" as I define it..."sway" (in my simple mind) being a back-and-forth movement that is self-sustaining or self-amplifying. The trailer doesn't sway. I don't know what to call it...what I DO get is a genuine 'tug' at the back of the truck when a large vehicle passes me. Once the vehicle passes, the trailer goes back in line and my corrective steering action ceases.

To digress: As the air is compressed between the other vehicle and my (any) trailer, the velocity increases. By physical law, the pressure decreases, sucking my (any) trailer closer to the other vehicle, be it a moving van, cube truck, or semi trailer. Forever and always, this will be the case.

The difference here is how the tow vehicle reacts. On a 5th wheel, it makes nary a difference. The trailer still gets sucked to the side, you just don't feel it or need to correct for it. In a bumperpull, it will always happen, but pickups just seem to "deal" with it better than my SUV. As I said before, perhaps it's a wheelbase thing, an IRS thing, a tire thing, whatever. Just trying to isolate and eradicate it is the issue at hand.

As I said, I'm not changing to 20" tires to fix this problem, but my thinking is that it won't hurt. And they are E load rated.

I generally don't 'correct' the trailer by pulling the lever on the controller at speed. Not exactly the time I want to take a hand off the wheel, if you know what I mean.

Hope that clarifies...

 

[Renze]

My previous job was at a builder of professional small trailers, e.g. 2000 to 3500kg bumper pull, and 5th wheel air brakes up to 12 ton. ( i say "professional" small trailers, as the bumper pulls of major brands were half the price of what we built, but ours would outlast them by a factor 4 so we only had customers that needed a quality trailer for everyday commercial use)

Once we had an Iveco truck which didnt have the towing specifications: The rear axle torsion bar was only 22mm, where a Merc usually had a 45mm when ordered with towing package. When they went to the roadworthiness approval to tag it, a truck passing by would suck the entire combination allmost two foot aside.
We had a lot of trouble with that customer, as the Iveco dealer said it was our fault because the axle placement of the trailer was wrong. We invited them over and put that trailer behind a Merc 518. It was a world of difference.

You can do all kinds of funny things to your hitch, but when moving the horizontal hinge point another foot and a half back with this hitch, you're loosing half so you must gain double, to get any better of it.

I would try to find some air bellows that fit inside the coil springs of your SUV (or if its leaf springs: just an Air ride kit from Firestone)
Stiffness of the rear suspension makes more difference than anything else. The cool thing about air is that it doesnt make an empty vehicle stiff. In fact we sold it as a means to make a Tundra (one of the few scarce imports into Holland) ride more comfy when not loaded: install the bags, inflate them untill they lift the suspension just a bit, and it will be smooth when not loaded, and will get stiff when its compressed under load.

 

[KeithInSpace]

...when moving the horizontal hinge point another foot and a half back with this hitch, you're loosing half so you must gain double, to get any better of it.

That was one of the questions I asked Hensley originally. On my truck, for some reason, I actually end up having to modify every draw-bar I've purchased. Because of the spare tire placement, this involves drilling a new retaining-pin hole further up on the hitch and lopping off as much as 6 inches off the truck-side of the draw-bar (otherwise, the un-used portion would run into the under-hung spare tire). Without doing this modification, the stupid ball would be sticking over a foot out from the bumper.

That said, the Hensley system sticks out a bit further, but IN THEORY it moves the rotation point 50 inches forward...far more than double.

I don't mind the idea of "bagging" my truck if I KNEW that would fix the issue. Sounds weird, but I don't mind throwing $3,000 at a Hensley if I KNEW it would fix the problem and would do that before I threw $500 at putting air bags in my rear suspension if I only THOUGHT that would fix the problem.

I certainly appreciate the thoughts...perhaps I'll ask the question in the RV forum. Bunches of those folks run Expeditions...perhaps they know something I don't.

 

[Sean Woodruff]

Hello, my name is Sean Woodruff. I am the former vice president of Hensley Mfg. that the company likes to lie about. I now make the ProPride 3P hitch; which is Jim Hensley's latest design.

I know the OP has talked to Hensley so I thought I'd chime in here.

Projecting the pivot point does make a huge difference in the stability of the trailer. I built the Hensley company to what it WAS and now have sold close to 1800 of my ProPride hitches and you will hear nothing but praise for Jim Hensley's hitches.

If you have any specific product questions, on either hitch, I'd be happy to answer them here for you.

 

[KeithInSpace]

I appreciate it, Sean. I hadn't gotten into direct comparison of the two hitches yet (the "old" and "new" Hensley, as it were), but I'm all about keeping it real. My kids are very excited about the upcoming camping season and I want to make it as safe as possible for all.

I look forward to calling you in the near future and learning more about your hitch. I probably won't pull the trigger for a few months at least, but I like having my research done so I don't make any rash decisions.

Hope all is well.

 

[burnetma]

I completely understand your concerns. I have towed well over 100,000 miles and sway can really un-nerve even the most experienced driver.

It sounds like you have an Equilizer style hitch.

I checked out the Hensley product and liked it alot, but could not justify the cost or the fact that it is one hitch for one trailer as I have 3 trailers. I purchased a Reese Strait Line with the Dual Cam sway control. It works perfectly for all of my applications. My tilt bed equipment trailer was absolutely unruly without the hitch dual cam sway control. I had it take off (swaying side to side across two lanes) with 125 bales of hay doing 65 mph on the interstate towing with my F250. That was way too exciting. I added the dual cam and now I honestly forget the trailer is behind me.

To answer your questions about your current set-up:
1. Yes, both the short wheelbase and the IRS is hurting the stability.
2. Yes, higher load rated tires will help stability.
3. Yes, too much tongue weight will also hurt stability especially with a light IRS suspension. Too little tongue weight is equally dangerous.

I am very confident that the Hensley will work well and you will be very pleased. I am also confident that you would be happy with the Strait Line set-up.

 

[KeithInSpace]

I very much appreciate the response. Good info.

 

[Renze]

Projecting the pivot point does make a huge difference in the stability of the trailer.

The idea of pivot point projection to increase towing stability isnt new: the standardised tractor 3pt system was invented by Harry Ferguson in the 30s and
had the same background idea.. However this is a totally different application of the concept..