Anti Sway Systems - Necessary or Marketing Con?

[4X4Dodger]

This may open a Pandora's box and bring down a lot of criticism on my head but the question really remains a valid one I believe.

Are Anti Sway bars (Like the Hensley) really necessary or a crutch for those that either cant drive a trailer effectively or have an out of balance rig? Are they a multi million dollar business out to convince you you really need one when you dont OR are they really filling a needed gap in TT towing safety?

First a little background: Despite my newness to this site, I have been towing trailers on and off most of my life (a good 45 years of driving) and towed everything from a small U-Haul to a 53 footer with a GVW of 80,000lbs. I have held a Class A CDL with endorsements for Doubles, Triples and Tankers for over 20 years and owned my own trucking company (10 trucks/25 trailers doing logistics) I have for a good share of my life lived overseas where I have seen every possible combination of tow vehicles and trailers most of which most Americans would be horrified to think actually are driven on the road.

No matter what I have towed or with what vehicle I have never felt the need for an Anti-Sway system. Right now I tow my 30 foot Gulfstream Innsbruck with my Dodge 2500 4x4 HD 5.7L Hemi.

I'd like to hear the arguments for and against. Are these systems just taking the place of proper training and practice or are they a true necessity? AND do they instill a "False sense of Confidence" when driving an unbalanced or badly loaded Rig?

NOTE: I am not trying to be willfully provocative here but am truly interested in your thoughts.

[rbpru]

My Blue Ox hitch is supposed to have a level of anti-sway built into it. On those occasions where I have had to swerve or brake hard I never had an issue. However, I am only pulling a 25 footer at about 6000 lbs. with an F-150 E-Boost.

As for how fancy a vehicle you need. In my younger years I was told that a Chevy cost the same as a Cadillac only longer. 😉

[stevec22]

4X4Dodger wrote:
Thanks to all the posters so far. There seems to be two common threads running through the comments:

Sway Control Systems are a "safety" apparatus that IS necessary

and those that say:

There nice to have but not really necessary with the right rig and set up. So why not use one?

What brought this to my mind was the disconnect between the relative weights of a class 8 tractor vs it's fully loaded 53'trailer and the relative weights of the average Travel Trailer setup. And the fact that our parents and their parents often towed large heavier trailers with just a stock sedan.

Your average Class 8 tractor weighs in at somewhere between 16k and 20K LBS. The trailer fully loaded would weigh between 60-65K This all together would give you a fully loaded 80k# vehicle. (approx)

That means that 60,000 lbs can be safely towed by a vehicle that weighs one third as much. I don't believe that the physics change as the numbers decrease. Of course there are many differences in the set ups of these two vehicle types. (pivot point to the trailer axle CL (center line) is the most important) But essentially they are a tow vehicle and a trailer.

My Dodge P/U weighs in at 9000# my trailer at 6292 empty and 8000# fully loaded...Maybe this is why I dont need sway control. But even if you have a big 5th wheel and a 3/4 ton p/u you should still be within the 1/3 - 2/3rds of the scenario above.

As for Tractor trailers swaying on the road. Doubles and triples do sway but it's because they are attached with two pivot points very close together and a steerable (ie turning) axle under the front of the trailer (s). Wind will definitely move a 53 foot trailer sideways, but I dont consider that "Sway" That is wind effect working on a gigantic sail made up of the side of the trailer. Sometimes empty a trailer will bounce from side to side on an uneven road surface but that isnt sway either.

So I am interested in what REALLY causes sway in these recreational rigs.
My guess is uneven loading, too short a distance from Pivot point to C/L of trailer axle, driving habits.

I notice that the European and Australian trailer tongues are quite a bit longer than most of ours and this would help reduce the tendency to sway as it increases the distance from pivot point to axle C/L. If you look at most older trailers from the 50's and 60's you will note that the axles on virtually all of them are much further back than the modern ones. This I believe is one reason many of those older trailers, which were quite heavy, could be towed by your average sedan.

After WWII my entire extended family, Mother, Father, Aunts and Uncles and Grandmother emigrated from Michigan to Southern California and they all pulled a house trailer as they were called then. My grandmother drove her '32 ford coupe pulling a quite big trailer...all the way down Route 66 to San Bernardino, Calif. No body had a sway control system....so what has changed? We have much bigger tow vehicles, lighter trailers, six or 8 speed transmissions instead of three or four, Were using huge diesel engines instead of a flat head six...It just doesnt add up to me.

A couple of points about your comments.

1. 5th wheels and tractor trailers are set up with a king pin and do not need sway control. Sway control is only needed for TT, as I understand the situation.

2. when your family traveled to CA in the 1940's, the speed they traveled was likely less than 45 MPH and the number of trucks passing them at 70 MPH were non existent. If you elect to travel back roads at 45 MPH, I think you could skip the Sway control.

[dave54]

I use one.

Regardless what others post here I will continue to use it.

I inadvertently started out one trip with it too loose and I felt it immediately. After pulling over and adjusting I continued on my trip it drove like a dream. Properly dialed in I do not feel the trailer at all. Rough curvy road, crosswinds, big tractor-trailers, et al do not affect the rig.

[JiminDenver]

We use a friction sway bar and one trip I didn't get it cranked down. I could feel the trailer move a bit when being passed by the big trucks, something I don't usually feel so it does make a difference. Using it I have had a gust of wind push the whole rig sideways but it didn't sway. Same is true with the WDH, we don't HAVE to have it, but it is better with it.

For those that think all you need is a big truck. We watched a F 250 pulling a trailer the same size or smaller than our on our way into work. He didn't need the WDH but he sure needed sway control. Every time he adjusted that truck in the lane the trailer would shimmy. Trying to change lanes caused it to sway until the back of the truck did too. It took a few attempts to completely change lanes at which point we got the heck outta there. I'd hate to see him on a windy day in the mountains.

[Speedogomer]

I'll put it this way...

For many years people drove without seatbelts, most of them are alive today, never had an issue.

For a long time cars didn't have ABS or airbags, most people who drove those cars are fine today.

Cars didn't have crumple zones, tow ratings were a recommendation, and WDH with sway control was unheard of.

People all the time like to use the argument "we never had those safety things in my day and I'm fine". That's because every person who isn't fine, is dead from the lack of safety equipment.

Its an additional safety measure, something you may not ever need, just like a seat belt. You may ride around for your whole life unbelted and be fine.

I'm a paramedic, and trust me when I say this, seeing just one dead kid face down in a ditch after being ejected from a vehicle because he was not restrained with a seatbelt... Makes you a believer in seatbelts. For every story that you have about " I know a guy who was thrown out of a car and would have died if he wasn't", I have 100 stories of people who would have been alive with just a headache if they were belted.

Point being, even with a large truck, its a modern safety tool and can help avoid trouble.

[4X4Dodger]

Thanks to all the posters so far. There seems to be two common threads running through the comments:

Sway Control Systems are a "safety" apparatus that IS necessary

and those that say:

There nice to have but not really necessary with the right rig and set up. So why not use one?

What brought this to my mind was the disconnect between the relative weights of a class 8 tractor vs it's fully loaded 53'trailer and the relative weights of the average Travel Trailer setup. And the fact that our parents and their parents often towed large heavier trailers with just a stock sedan.

Your average Class 8 tractor weighs in at somewhere between 16k and 20K LBS. The trailer fully loaded would weigh between 60-65K This all together would give you a fully loaded 80k# vehicle. (approx)

That means that 60,000 lbs can be safely towed by a vehicle that weighs one third as much. I don't believe that the physics change as the numbers decrease. Of course there are many differences in the set ups of these two vehicle types. (pivot point to the trailer axle CL (center line) is the most important) But essentially they are a tow vehicle and a trailer.

My Dodge P/U weighs in at 9000# my trailer at 6292 empty and 8000# fully loaded...Maybe this is why I dont need sway control. But even if you have a big 5th wheel and a 3/4 ton p/u you should still be within the 1/3 - 2/3rds of the scenario above.

As for Tractor trailers swaying on the road. Doubles and triples do sway but it's because they are attached with two pivot points very close together and a steerable (ie turning) axle under the front of the trailer (s). Wind will definitely move a 53 foot trailer sideways, but I dont consider that "Sway" That is wind effect working on a gigantic sail made up of the side of the trailer. Sometimes empty a trailer will bounce from side to side on an uneven road surface but that isnt sway either.

So I am interested in what REALLY causes sway in these recreational rigs.
My guess is uneven loading, too short a distance from Pivot point to C/L of trailer axle, driving habits.

I notice that the European and Australian trailer tongues are quite a bit longer than most of ours and this would help reduce the tendency to sway as it increases the distance from pivot point to axle C/L. If you look at most older trailers from the 50's and 60's you will note that the axles on virtually all of them are much further back than the modern ones. This I believe is one reason many of those older trailers, which were quite heavy, could be towed by your average sedan.

After WWII my entire extended family, Mother, Father, Aunts and Uncles and Grandmother emigrated from Michigan to Southern California and they all pulled a house trailer as they were called then. My grandmother drove her '32 ford coupe pulling a quite big trailer...all the way down Route 66 to San Bernardino, Calif. No body had a sway control system....so what has changed? We have much bigger tow vehicles, lighter trailers, six or 8 speed transmissions instead of three or four, Were using huge diesel engines instead of a flat head six...It just doesnt add up to me.

[nevadanick]

I have no need for sway control but would like to know where i can get the fancy truck for 45k.

[GrandpaKip]

I really can't come up with a reason not to use a sway control on any camper. I have never had a sway problem with the 3 campers we've owned, but it doesn't mean it can't happen, especially in emergency situations. Just another reason I went with the Andersen hitch.

[BurbMan]

Ivylog wrote:
If you used that big storage area behind the axles for heavy item it's going to take you to the scene of the accident regardless of sway control or not.

So thanks for not reading my post. We DID use that storage area, in fact it was packed to the ceiling and wall to wall. We towed that Sunnybrook for thousands of miles the 5 years we had it and never had any sway, not even a wiggle. I even towed it through a snow storm on icy roads when we had to detour a spring vacation enroute to go north into upstate NY for a family emergency.

Believe what you want to, but the 4-bar design of the Hensley and ProPride work to prevent sway, regardless of tongue weight, it's just that simple. If you want to dive into the engineering of it, look for the sticky at the top of this forum regarding "How does the Hensley really work?"

[CampingN_C_]

I too have held a Class A CDL and towed all types of trailers. I pulled my last combo once on a short trip with no sway control OR WD and it pulled the same as fully hooked up. However, my current setup seems to be more picky and I've had sway issues.
So yes, IMO sway control is a necessity in some/most applications.

[Ivylog]

Like the OP I've been pulling all types of trailers for decades and only one came with a sway bar which I used since it was there although it was a 31' Airstream that really did not need it.
When I can see the rigs of those that say you have to have sway control (from previous posts too) I can see why... the tail is going to wag the dog. If you have a long wheel base TV that is not maxed out and plenty of tongue weight you do not new sway control. If your TV is marginal then you need all the help you can get but it's really just a band aid.
I've seen too many pictures of wrecked TT trailers that had some type of sway control still on the tongue. If you used that big storage area behind the axles for heavy item it's going to take you to the scene of the accident regardless of sway control or not.

[BurbMan]

4x4, that's a valid question and one that's been asked here several times over the years. In a nutshell, there are just too many variables to make a blanket statement as to whether an anti-sway mechanism is "required" or even a good idea.

If your rig tows fine without anti-sway and you are comfortable driving it, then I would say you don't need one. I'm with Doug33, I think it is good insurance.

We bought the Hensley when we got our second TT, a 34' Sunnybrook bunkhouse. We loved the floor plan with 4 bunks for the kids and the storage was amazing! The entire area under the bunks was clear storage:



In this pic you are looking in through the curb side access door, the one across is the other side of the TT and the one to the left is the rear of the TT. So we had this giant 6'x8' storage space that got filled with tables, chairs, generator, BBQ, fire pit, etc., etc. The only problem was all that storage was at the very back of the TT, well behind the axles....so you know what that did to the tongue weight. Even with an extra battery and stuff under the front queen bed, tongue weight was barely 10%. Point being that NOT every TT made today is designed with good or even acceptable weight/balance.

What we found with the Hensley was that towing was much more comfortable...the 4-bar linkage is not sensitive to tongue weight so loading/weight/balance on the TT were not as critical as they were before. Even though we were within all of our ratings, the TT scaled at 8500 lbs and the burb at 8600 lbs, and the burb has a relatively short 130" wheelbase to control a long TT. (GVWR=8600, Tow=12000, CGVWR=19000)

We found that situations on the road had zero affect on the trailer, things like uneven pavement in construction zones, high cross winds, wet roads, passing semis, etc. I can tow the TT all day at 65-70 mph in any conditions with two fingers on the wheel, just like driving with no TT attached. I won't say "you don't know it's back there" because obviously that is BS...of course I know it's back there, but what's different is that I don't have to worry about what it's doing. With the Hensley, I know that the TT isn't doing anything but following the truck in a straight line.

I even got my wife to tow a few hours on the road, and she was able to handle the rig just fine, having never towed a trailer behind anything in her life.

I know folks on the forum here like to call hitches like the Hensley a "band-aid" that simply masks the conditions of an unsafe set up. Fact is, we don't "need" a Hensley hitch, we could tow our TT just fine with a conventional hitch. Of course we don't need a TT either....we chose to buy one because we like to camp. Likewise, we chose to buy our Hensley hitch, because for us it gives us peace of mind knowing that hitch has the TT under control at all times and in all conditions. For us, going camping is about relaxing, and the Hensley makes the tow there smooth and uneventful.

I'm not suggesting that everyone should run out and buy a Hensley, just trying to explain why I bought one. If you're happy with how your rig tows today, then I would say you're all set.

There are only 3 hitches whose design truly prevents trailer way: the Hensley Arrow, the Pro-Pride 3P and the PullRite. These hitches definitely work as advertised, but that's not to say there isn't a certain amount of marketing hype in anything you buy that's RV-related.

4x4 also makes a good point about complacency, and that is always a risk.

[TomG2]

TenOC wrote:
We (all of us) instead of purchasing a "work truck" with no extras for $25K we buy one with the fancy radio and fancy seats (none of which are "required") for $45K. ...snip.....

How can you speak for "all" of us. I see lots of work trucks and modestly equipped tow vehicles in the many parks that I visit every year. Quite a big generalization.

[TomG2]

Trackrig wrote:
I drive a DP, but I can tell you that more people should be using an anti-sway system than are using them now. We're usually traveling about 62 - 66MPH and we're often passed by someone with a TT that's going side to side from one white line to the other - and sometimes further sideways then that.

I wonder if those people never look in a mirror or what? I usually slow down and let them get by me as soon as possible and way ahead of me. If they're going to wreck, I want them a good ways out in front of me so I have time to avoid them.

Bill

There is a saying that you cannot fix stupid and I will add incompetence. If people are swaying from shoulder to shoulder as you say, then no hitch is going to cure all their problems. BTW, I tow thousands of miles per year and see just as many stupid drivers whipping through traffic in big motorhomes. Having either is no assurance of competency.

[TenOC]

We (all of us) instead of purchasing a "work truck" with no extras for $25K we buy one with the fancy radio and fancy seats (none of which are "required") for $45K. The same for a TT. We purchase one with all the fancy (not required) extras. But we will not spend $2-3K for an outstanding hitch that WORKS. Not only is the hitch safe, it makes towing a TT a task that your wife (and you) will enjoy while you see the USA.

Having said the above, would I purchase a Hensley if I was only going to tow the TT to the local campground (a few 100 miles) once or twice a year? I do not know. If I could find a good used one -- yes, a new Hensley, I do not know.