Getting sucked in - Stablizer bars or not?

[FordTruck]

OK, OK OK don't get excited about my subject title. It was just a grabber !!!

We've got a 22' Airstream TT (5000GVWR) and pull it with a F-150 5.4L (Max 7800) & weight distributing hitch but no stabilizer bar between the hitch and the trailer.
The trailer tows easy and straight, except when on the highway when being passed by big rigs (18 wheeler types). I'm finding that as the trucks approach from the rear and begin to pass, the air pressure pulls the trailer and F-150 toward it.
My question is, would a stabilizer bar make any difference? If so, how and why? If not, thanks anyway.
For now, I'm keeping a sharp eye out in my outside mirrors and holding tight and steady when the big rigs approach.
Thanks,
FT

[azflycaster]

Good question. My setup is about the same as yours and I do get sucked in as well. I think everyone gets it to some degree. Have you ever stopped on the side of the interstate and gone into the trailer for something? When a big rig goes by the trailer really does a shake job. I also wonder if a friction sway device would eliminate some of the suck.

[LI Pets]

I sometimes drive a 15' cube van E-450 with a power stroke going up/down RT 95 to Fla.

This truck does 75 easy, when I see a trac/trail coming up from behind passing, I slightly steer to the right maybe 18" over. It helps a lot.

Funny thing is when you get sucked in (not paying attention, it brings you close then pushes you away----really strange.

[NorCal Bambi]

FordTruck, If you can have ToAir explain the Hensley hitch to you. From my understanding of its physics it will solve the problem. It's not cheap by any means. Here is ToAirs information. http://www.airforums.com/forum...irishuman.html
Tell him Don " NorCal Bambi" says Hi.
Don

[moosetags]

I didn't like the "suck 'n push" either. I got the Hensley and it's totally gone. I no longer pay any attention to 18 wheelers coming by me.

[eubank]

We've got pretty much the same and had the same problem. I added a stabilizing bar that we picked up from Ebay, and it did help some. It's not like the suck-in disappeared entirely, and caution is still in order. But it did help somewhat.

Lynn

[85MH325]

The push-pull you feel is a function of the 'high-pressure/low-pressure' 'bow-wave' of the trucks. How the front end of the truck is designed, the speed of the truck, and the direction and speed of the wind relative to your rig will determine how badly you're affected by it. If you haven't eliminated the basic causes of sway in your rig: e.g. load balancing; proper tire inflation on both TV and trailer; adequate tongue weight; good shocks, poor TV suspension engineering; etc. etc. etc., then that 'push-pull' can potentially set you up for a sway episode; especially if you don't employ some type of sway-control.

Sway control can't eliminate the 'push-pull' effect, but it will cause your entire rig to be affected as a single 50' unit rather than two 25' units with a hinge in the middle.

All of the good quality sway-control hitches will have that effect when employed properly. Even just having a friction sway control bar, properly set up, will help as well.

Hope that helps!

Roger

[Mike Lewis]

Originally Posted by NorCal Bambi

FordTruck, If you can have ToAir explain the Hensley hitch to you. From my understanding of its physics it will solve the problem. It's not cheap by any means. Here is ToAirs information. http://www.airforums.com/forum...irishuman.html
Tell him Don " NorCal Bambi" says Hi.
Don

I have often wondered if a Hensley would eliminate that. Have used a friction sway control and found it to be only a slight improvement. We now have a dual cam reese which greatly improved this and feel quit comfortable in wind and with trucks passing. Still I don't have the feel that Hensley owners discribe. I would like to hear them discribe the same condition.---pieman

[Condoluminum]

You might also consider higher tire pressures in the truck when towing, as well as anti-sway bar... The pull towards a passing truck and then push towards shoulder of highway when trailer gets ahead of yours is undeniable aerodynamics, and one of the challenges of towing long trailer with vehicles having short wheelbase.. The experience in an old Bronco with loose steering gear was "special.."

Pumping up truck tires, adding anti-sway and keeping trailer tires well inflated reduced the probmlem dramatically..

JohnMcG

[mustang]

I think your tow vehicle is fine a stabilizer is a good Idea However dont forget the 8 to 10 percent on the tongue rule. Guessing if your trailer weighs in at 5000 lbs then the Pin or Hitch should be at 500lbs, of course using the stabilizer bars to redirect the weight back and forward.If you dont use the 10 percent rule you will get squirlly all the time. Hope this helps

[2airishuman]

hi fordtruck...

as roger suggests there are many issues related to how your rig handles this push/pull and how you react when it happens....his whole list matters.

tire pressures may be the easiest and most effective first step...

everyone wants a smooth/soft ride, many reduce tire pressures to achieve this...others just don't check pressures often.

suspension components, steering geometry and worn parts are also a big issue.

your rig dimensions, mass and center of gravity also are important...

so a tall, short, high cog with soft tires and worn suspension is gonna be pushed around more. and an inexperienced or unattentive driver is gonna react badly too....

it is easiest for me to think about turbulence, bow waves and the venturi effect by looking at boats in the water....we can see it as well as feel it in that medium. the pushing/pulling forces are right there in the wake/waves!

a building attached to the shoreline or other fixed/rigid structures still move/react to bow waves...and wear/decline as a result of big bow waves...

so hensley rigs feel it too...
but the chain of reactive forces is different
and usually the driver imput is less dramatic...
these are good things...no terror, no death grip on the wheel.

several haha users have desribed what they feel,
some have described why the forces are different.
i'll try to post some of that for you, mike and others
in the ultimate haha users guide.

cheers
2air'

[DavidsonOverlander]

Originally Posted by Mike Lewis

I have often wondered if a Hensley would eliminate that.

In my experience the Hensley does eliminate the problem. I don't feel any pull from trucks passing. The difference in air pressure must still be there, but the force of it is not transfered to the tow vehicle.

[marinanc]

Two weeks ago I picked up, new to me, 2001 Excella 28' and had same problem, even with new Reese dual cam hitch. I was nutz for buying it when I only have a 5.9L half ton shortie for towing, so now I'm looking for bigger, better tow vehicle. Hope this helps some others hoping to purchase "big" trailers with small wheelbase tow vehicles.

[85MH325]

Originally Posted by DavidsonOverlander

In my experience the Hensley does eliminate the problem. I don't feel any pull from trucks passing. The difference in air pressure must still be there, but the force of it is not transfered to the tow vehicle.

Grant (and all...)

A hitch, of whatever variety, cannot stop air from acting on the tow rig. You have almost an ideal setup with a 26' lightweight Overlander with tandem axles and a long wheelbase, heavy tow vehicle. Frankly, any sway control hitch setup would work well for you, provided that you have taken care of all of the other 'stuff' that contributes to a sway episode.

While it may feel like the Hensley has taken all of the problem forces away, they're still there; they're just acting on the entire rig rather than on portions of it at a time. 2Air is absolutely correct when he talks about driver over-reaction as well. Sometimes we're our own worst enemies.

A Hensley is a very cool piece of engineering. It effectively transfers the pivot point of the hitch from a point several feet behind the axle (giving the trailer leverage on the tow vehicle) to a point at or near the center of the differential, the idea spot where the trailer has a much more difficult time leveraging the rear axle. Hensley hitches are, however, expensive and heavy. If you insist on towing a long, heavy trailer with a short wheelbase lightweight tow vehicle, the Hensley is an excellent choice. If you have an adequate tow vehicle for your load, and all of the other factors that contribute to sway are eliminated, then any sway control hitch will do the job for you very nicely.

Hensley has marketed their hitch as the 'cure-all' for all kinds of problems. Actually what it does is masks those issues. Most of those problems can be resolved simply by maintaining your tires and tow vehicle, and loading and balancing your trailer properly.

The causes of sway are manifold, and they scare folks silly, but if you troubleshoot your situation and eliminate those potential causes one at a time, the Hensley can be considered a really nice luxury rather than a necessity.

Roger

[scottanlily]

I will agree with the previouse posts ,no more to add ,but to say on a past trip to calico ghost town out by needles off I 40 we had to drive north of the
interstate and head for the hills so to speak (calico is in the hills) the crosswinds were tremendouse ,and the travelall and trdwnd handle it great
I was ready for being blown around sideways but no trouble .yes could feel the wind some ,but the airstream design came full view as the wind rushed around and over its smooth shell as designed .What a good feeling! We did not get that blown around drama as you can feel with a square trailer.
Traveling on a stream of air ....almost

Scott