How essential is the sway bar?

63overlander · 06-30-2004, 05:01 AM

Hello again to everyone. It has been some time since I last posted, at that time asking about the advisability of using an ambulance as a tow vehicle. As an update, I did bid on a 1984 E350 ambulance with 37,000 miles on it and with a 7.5 litre gas engine. I won the bid with $3,333.33 and other than Miss Piggy being a very thirsty girl am happy with the purchase. I have been turning the interior in back into a kind of camper for one old guy for the times I don't drag the 63 Overlander behind. I picked up an appropriate heavy duty hitch receiver for fifty bucks and yesterday purchased a used reese load equalizer for one hundred twenty five. Now I need to determine if the anti sway bar is essential and if so, should it be the friction type or the dual cam type? My trailer tongue weight is 600 to perhaps 700 pounds and overall weight somewhere around 6 thousand pounds... say seven thousand with a load. The standard spring bars on the equalizer are rated at one thousand pounds (says so on the bars). I read somewhere in an ealier post that they may be too stiff for the tongue weight of an Overlander, so would it be wise to get the bars rated at 750 pounds? I am an elder on disability and thus don't have money to spend for the heck of it. On the other hand I don't want to be standing by the road in Arizona looking at a mooshed silver twinkie either. So, to repeat the basic question... how essential is an anti-sway device? I don't expect to go over fifty five miles per hour anyway, so do I really need it? As always, I am grateful for the sage advice of my Airstream compadres...
SilverBear

Navigator · 06-30-2004, 06:13 AM

SilverBear, I bought my 31' Airstream in MN and towed it to DE w/o sway or equalizer bars. NEVER went over 55. Towed fine except when Big semi,s passed me doing 80. Of course this was all interstate. I now have a Reese with anti sway cams. Works great.
Dick

Princer · 06-30-2004, 07:05 AM

Undamped sway is a major couse of accidents and trailer turnover. I would not tow anything over 3000 or 4000 pounds without an anti-sway system. Without it you will always have some small sway and occasionally get a big push. But you can never anticipate when the "really big problem" will occur. Not worth the risk.

TomW · 06-30-2004, 09:04 AM

For the record, I have a Reese, dual-cam anti-sway weight distributing hitch, and plan to always use it while towing my Overlander. But what gives me the safest feeling while going down the road is the fact that I am in a 3/4 ton Suburban which is heavier than my Overlander. It is so massive I could probably tow without weight distribution.

Uncontrolled sway is more likely to happen when the tow load is heavier than the tow vehicle. It is also more likely to happen while towing with a 1/2 ton truck because the tire sidewalls generally have more give.

63overlander is towing with a 1984 E350 with a 7.5 litre gas engine. With a full gas tank

, that has to be some serious mass. For short, low speed trips, I cannot see him having sway problems. For longer, posted speed limit trips, I would recommend the Reese dual-cam anti-sway.

Tom

Leipper · 06-30-2004, 10:05 AM

Uncontrolled sway is well telegraphed by the rig handling in normal circumstances and the risk of such sway can be greatly reduced by proper driving habits. Sway control mechanisms are more for comfort than for catastrophic event prevention.

In other words, how does your rig handle on the road with your current hitch? If it is squirrily then you should consider doing something. First is to make sure you have tires with stiff sidewalls inflated to max rated psi. Second is to make sure your load is properly distributed. Third is to make sure you have good suspension for handling. If none of these work, then look at adding sway control mechanisms.

In your case, the dual cam is probably the best bet. I don't think the friction bars are worth much. I would have gone for the Equal-i-zer from Lindon as a first choice from scratch, though.

And, if you are paranoid and have a lot of money or have an underwhelming tow vehicle and a lot of money, the Hensley or Pullrite would be a nice solution.

One big factor is the differential to ball distance. If your van is an extended type this is rather long (like my B190) and that can aggravate handling problems.

63overlander · 07-02-2004, 02:32 AM

Once again, I want to thank all of you for responding to my question. I can see that the sway bar is essential and that I'll be in the market for a dual cam type. Thanks for saving me from problems down the road...
SilverBear

Pahaska · 07-02-2004, 09:23 AM

Quote:

Once again, I want to thank all of you for responding to my question. I can see that the sway bar is essential and that I'll be in the market for a dual cam type. Thanks for saving me from problems down the road...

Good decision. About 18 months ago, a new couple joined our WBCCI unit with a new 25' Safari, towed by a GMC van with no sway control. They had never towed before and, somehow, our unit mentoring program didn't pick them up as it should have; no one noticed the lack of sway control. On the way home from that rally, in a construction zone, they were passed by an 18-wheeler and sway started. The van and trailer both rolled and were totalled. Injuries, were fortunately limited to a cut arm from broken window glass.

The couple is still with us; they moved to an Airstream motorhome. As a result of the accident, our unit is now much more aware of mentoring new members.

71_safari · 07-02-2004, 05:20 PM

I just don't understand all this fear about towing without sway control. Why not try it first? I tow without either sway or WD - never even a hint of a problem, although admittedly my Safari is only 23' and weighs somewhat less than an Overlander. And I make sure I have at least 15% on the hitch. But an E350 is even bigger and I bet wouldn't have a problem either. It certainly has plenty of mass, a long wheelbase and stiff tires.

I think most of these "sway disasters" are from people who are not paying attention to conditions and then panic and brake, or make abrupt steering corrections after a truck goes by with a higher than normal "bow wave" coming off the front. Or maybe they have an unbalanced rig (tail heavy) which will react badly also. Airstreams generally tow really well due to the aerodynamics and the tendency to have a higher than normal tongue weight.

Pahaska · 07-02-2004, 06:47 PM

Quote:

I think most of these "sway disasters" are from people who are not paying attention to conditions and then panic and brake, or make abrupt steering corrections after a truck goes by with a higher than normal "bow wave" coming off the front.

bad advice! You never let your attention wander? You never get surprised? Some other idiot never forces you into an evasive manouever?

The sway control is the backup for the inevitable times that folks do get caught unaware or are forced to evade.

A recent example for me was an incidence of road rage directed at a 3rd party. A young woman had just passed me on the left when the "road ragee" tore around me at high speed on the right on an exit laneand cut right into me. Only a yank on my wheel kept him from tearing my fender off. For the next 5 miles, he harrased that woman, cutting her off repeatedly and even threw objects at her car. Unfortunately, There was no way I could have anticipated having to yank my wheel over; in the lane he was driving in, he should have exited.

My Classic 25 tows like a dream, but I was very happy to have the backup of the HD Dual Cam. At that moment, it was the best $153 I ever spent.

71_safari · 07-02-2004, 07:49 PM

I hope you were able to call 911 on the jerk.

I suppose I hadn't really given much thought to a sudden evasive maneuver, although I have switched lanes pretty quickly a couple times and the Safari has always followed along pretty well. But I can see how one might snap it too hard and have the trailer come around in an oversteer situation, either on the original steering input or when trying to correct back the other way.

My understanding is that the intent is to dampen out changes in angle between the trailer and TV along the horizontal axis. But if it were stiff enough to actually resist a relatively small change in angle, of such a substantial mass, wouldn't it also resist normal turning to some degree? Like around town, where the angles are much larger? Wouldn't that force the towing vehicle to understeer when making turns, since the hitch is resisting and the trailer wants it to go straight?

On sporting motorcycles we frequently use steering dampers to dampen out high frequency oscillations in the bars, which is easy to do because under normal driving, bar input is very low and in a "tank slapper" it is extremely high (think shopping cart wheel). But I can't imagine a trailer oscillating at anywhere near that rate of several times/sec.

Is it just for emergency use then? To prevent losing control when making evasive maneuvers? I could understand the value if that is the case, but I still think there might be an undesirable effect at low speeds/around town.

sorry for thinking out loud.

Tarheel · 07-02-2004, 09:35 PM

Pulling a 34' that weighs in just under 10,000 lbs, tongue weight is less that 800, can't get anymore weight on it, have reese equalizing bars as well as an anti sway friction device. The Dodge Cummins weighs in at 7200 lbs. I have towed about 40,000 miles with this rig. I have forgotten to tighten down the friction sway control several times and really could feel no difference, but when I made my first stop and walk around I caught it and tightened it. My 250 hardly moves at all when I drop the trailer on the ball but I would never even consider pulling without the equalizer hooked up and this is a 3 axel trailer. The right rig passing at just the right speed still causes me to move a little. I usually see them coming but every once in a while one will slip up on me specially the box vans, new car carriers and certain flatbeds. Hooking up the equalizer and sway control is a small price to pay for saftey.

Tinsel Loaf · 07-03-2004, 06:20 PM

We use the Reese friction anti-sway bar and eventually you will find what the best setting is for your tow rig and AS to reduce sway. It took us a while to get it our tuned to the right friction setting, but it really has saved us in difficult traffic situations. Just remove it in while driving in the rain or before you back up making tight turns, like backing into your driveway.

Silvertwinky · 07-03-2004, 07:18 PM

Quote:

Originally Posted by 71_safari

I just don't understand all this fear about towing without sway control. Why not try it first? I tow without either sway or WD - never even a hint of a problem, although admittedly my Safari is only 23' and weighs somewhat less than an Overlander. And I make sure I have at least 15% on the hitch. But an E350 is even bigger and I bet wouldn't have a problem either. It certainly has plenty of mass, a long wheelbase and stiff tires.

I think most of these "sway disasters" are from people who are not paying attention to conditions and then panic and brake, or make abrupt steering corrections after a truck goes by with a higher than normal "bow wave" coming off the front. Or maybe they have an unbalanced rig (tail heavy) which will react badly also. Airstreams generally tow really well due to the aerodynamics and the tendency to have a higher than normal tongue weight.

I would like to direct you to a thread I posted on about an almost disaster we had. I didn't have sway bars at the time but not long after it happened I did.

Hey 63overlander,

After I got my dually I couldn't believe the difference I had in having good control. However, I still wouldn't want to travel with out any sway control. I think when you tow with your vehicle (assuming you have duallies) you will see the difference. However, as I mentioned in the posting I directed "71 safari" to, there are so many factors involved that I think only you will be able to evaluate your situation the best.

JohnG · 07-04-2004, 02:37 AM

nope, nope no way. Even if only going a few miles it's worth the time to hook them up.