Trailmanor accident on rv.net message board

I came across this and thought I would share.
The link is
http://www.rv.net/forums/index.cfm/f...nePage/Yes.cfm

Thanks for the interesting thread regarding the "tail wagging the dog".  Hank2 was using a Ford Ranger pickup with a standard hitch, towing a 2720SL which flipped him.  

I also use a standard hitch and have felt on occasion the kind of sway oscillation that could lead to trouble.  It's the sway where one excites it further by loosely correcting back and forth with the steering wheel.  Because of this I removed the spare tire off the rear and one of the two forward batteries.  This condition is now is improved.  I cautioned in a recent thread about adding weight at the ends of the trailer.

Sway is complex interaction between the two platforms, including suspensions and various moments of inertia -- and is not a black and white comparison of specifications such as wheelbase, weights, and towing ratings.  However, a lightweight tow vehicle such as a Ford Ranger using a standard hitch can make a non-ideal tow combination into real trouble.

Lighter vehicles especially need an equalizing hitch.  

wow. thanks for posting the thread on the TM accident. i plan to show it to dale when he returns home(half dead from being a CPA--he fell asleep at the wheel coming home last night--i plan to follow him home tonight)--anyway, i want to put this matter before you fellow TM owners. we have not yet gone on a long trip with our TM 2720sl--just to our close canyon and back--few miles.
this thread makes me wonder--do you think a toyota land cruiser, which weighs 5000# unloaded, has a 112.2 wheelbase poses a threat? it has towing pkg for 6000# and the engine is a straightline 6, 273.1 CID. we were told by our dealer a sway bar would probably not be necessary, too. we load our vehicle with lots of gear for fishing, backpacking, canoeing, biking. usually not all at the same time, but when going to south dakota, we do.
i would appreciate comments-many of you seem to be quite knowlegeable on this board.

sally swan

Sally,

Since you presently tow this combination and you're following guidelines, your best information is at hand:

How stable do you feel on the road?  
Have you practiced and are you confident with quick manuevering and emergency stopping?

Sally:


I don't know if you are using a weight distributing hitch, or not. Please forgive if I missed it.


If you are, it is easy to add a friction sway control to it, for about $100.00 . Or, there are a couple weight distributing hitches with a built-in sway control. Equal-i-zer, and Rease Duel-Cam, come to mind. (I used to use the Equal-i-zer myself).


Even if you do not need, and are not using, a weight distributing hitch, you can still add a friction sway control to your rig. You can get a draw-bar for your receiver with a small bracket and ball mounted to the side of your large trailer ball. Mount your friction sway control to your trailer tongue, and pop the end of it on that small ball.


If you do add, and use, a friction sway control, might want to un-hook it when you back into your campsite or driveway. If you turn too sharp with one, it could, (could, not would), bind up, and you could tear it up. So, maybe un-hook it, just in case. Won't take but a minute.
 

For about $100.00 think of it as cheap insurance. Better to have it, and not need it,,,,, then to need it, and not have it.


Mack

mack and jeober,
husband agrees, and we intend to get a sway-bar set-up. we'll go to our dealer to find out if our valley hitch is a weight distributing hitch. thank you both for the helpful comments. you're right--good insurance. happy trails, sally and dale ;D

and thanks, brian, for printing a link that may save at the least a ruined trip. 2swans

  Having read the posts about Hank2's accident on RVnet and those about the accident on this forum, it seems to me that many RVers feel that a mismatch between a heavy trailer being towed by a light vehicle might induce swaying. If this has become a commonly held conclusion, then it is incorrect. The size and weight of the towing vehicle has little to do with inducing swaying of a trailer. Swaying of a trailer results from its lateral instability on the road surface over which it is being towed. A well-designed and maintained large trailer that is properly loaded will not be susceptible to swaying when road conditions are good. On the other hand, a poorly designed or poorly loaded small trailer may be capable of severe swaying even under the best driving conditions.
  I can tell you from experience that this is true. Over 30 years ago the first trailer I ever towed was an 6' long box trailer that my wife and I rented to haul some of our belongings from California to Texas. Out in the countryside just a few miles down the road I felt the trailer wagging from side-to-side. This wagging worsened and I felt the rear wheels of our Buick station wagon moving side-to-side in rhythm with the trailer. I quickly learned that braking made it worse; fortunately I quickly discovered that taking my foot off the accelerator, downshifting into a lower gear and then accelerating stopped the swaying. We continued this way for hundreds of miles - until, somewhere in New Mexico the right wheel of the trailer came off. This occurred, fortunately, while we were driving slowly through a road construction detour. The mechanic dispatched by the national rental agency found all of the wheel's lugs sheared off! I suspected that the frequent bouts of swaying had put severe stresses on the lugs. On another occasion while towing a load of lumber in my own 6' box trailer, I experienced severe swaying that blew out one of its tires. After changing the tire, I drove home at a snail's pace to keep the swaying under control.
  I am not stating that the weight and power of the towing vehicle is not important. It is, but only in determining the extent of damages that can result from a trailer's swaying. That is, the heavier the vehicle the less likely it is that it will be pulled out of control and overturned by a swaying trailer. This is where the match between trailer and towing vehicle makes a difference where swaying is concerned.

There are many factors that can lead to a trailer's swaying: lack of auxiliary brakes on a trailer, improperly adjusted brakes, slippery road surfaces, poor tires, high winds, etc. In a well-maintained trailer the one other factor under the driver's control is the location of the trailer's center of gravity. When loading a trailer drivers should keep in mind that most of the load (and therefore its center of gravity) should be located forward of the trailer's axle. Exactly where this should be will differ from trailer to trailer. Suffice it to say, TrailManor recommends that the (trailer be loaded so that the) weight on the tongue should be approximately 10% of the trailer's gross weight. A TM trailer loaded like this will be laterally stable. As the center of gravity is moved farther back, less stability can result. Finally, if enough load is placed in the rear, the center of gravity can be moved rearward of the axles. This results in an extremely unstable towing condition, with swaying imminent the moment any lateral forces (wind gusts, going around a curve, etc) are exerted on the trailer. The reasons for the instability have to do with lengthening the moment-arm of the center of gravity as it moves to the rear. The greater the moment-arm of the center of gravity, the more its tires have to fight to maintain forward motion and minimize swaying.
  You can demonstrate this to yourself by taking a broomstick and tying a 1 pound weight on its far end. Your hand holding the near end of the stick simulates the hitch; your other hand farther up the stick simulates the trailer's wheels. As you swing the 1 pound weight slightly from side-to-side, judge how much force both hands must exert to resist the inertia of the weight. This is similar to an unstable, rearward center of gravity. Then untie the weight and retie it about 18 inches from the near end. Now straddle the weight with your hands and repeat the swinging of the weight from side-to-side. It should now be evident to you that your hands can much more easily control the side-to-side inertia of the weight. This is just like towing a stable trailer with a properly located center of gravity.
  If you tend to load up your TM with lots of heavy items, you might consider weighing your goods and purchasing a tongue scale. That way, you can at least assure yourself that as you maintain the proper proportion of weight on your hitch, you'll be keeping the trailer's center of gravity about where it should be. ;D

On the stability of a tow/towed package.  I have towed a variety of trailers over the years of varying configurations.  Never had a bad experience, although did experience incipient (Where is that spell checker?) sway tendancy.  I came away with the impression that my response on the steering wheel made a difference as to whether the motion was damped out or increased.  One question I wish to raise is that of the condition of the shocks on the towing vehicle.  The shocks are one of the mechanisms designed to remove energy from the system.  They should be maitained in good condition for towing.  Possibly a stiffer shock would be worth considering.  Anybody have thoughts or knowledge on this.

I am using a library computer to write this and my time is up.  So Bye.  

Larry's explanation is 'right on' albeit lengthy.  He covers the subject accurately.

I would add 3 comments:
First, if you are going to err on the percentage of tongue weight (he said 10%) make it more.  It won't hurt to have 15%, for example, but it could have disasterous results if you drop significantly below 10%, as he stated.  :'(

Secondly, I added a friction sway bar to my 2619, more for piece of mind than necessity.  However, the wind effect from big rigs became a non-issue after I added the sway bar.  

Finally, if you should EVER have your trailer begin to sway on you, the first thing to do is lightly apply the TRAILER BRAKE manually to slow down the entire rig... not the tow vehicle brake.  Normally, if the trailer is prone to sway on you, it will occur while you are going down a hill (as opposed to flat terrain), so downshift to keep your speed maintained to minimize using the tow vehicle's brakes and apply trailer brakes only if you detect any sway.  Then, bring the entire rig to a safe stop off the side of the road and inspect all your wheel lugs, reset your load (if it shifted) so that 10-15% of the total trailer weight rests on the tongue (hitch).   8)