Spring Bar overkill

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celticnomad

Member
Joined
Nov 8, 2010
Posts
6
Location
Scottsdale, AZ
Hello All,
I've read several posts on WDH and checked the library and have come away with the opinion that this is a topic with no pat answer. With that said I'll post my situation.

We inherited the hitch package with our purchase of a 2011 TT, a Husky Round bar with sway control purchased by our seller at the dealership where she purchased the TT. My concern is this. Are the spring bars rated at 801-1200# overkill for a TT with weight listed below?
My own feeling is this situation is possibly having a deleterious effect on the TV's suspension and feel the ride is very tight.
I am aware Husky has three ranges of spring bar, 400-600, 500-800, and what yours truly owns, 800-1200.

Here's some CAT scale numbers day before departure on a recent trip, GCWR 9680#, TV 5270#, the TT is then 4410# with 3980# on the trailer axle and 430# on the tongue. 5600#s of TV gvw was then divided between 2980# on the steer axle (3160# rated, close to maxing out :eek:) and 2720# drive axle (3760# rated). There was no water on board but the trailer and TV were loaded for departure.

Even hauling water (240#) am I not better off taking it down to 500#-800# spring bars?

Thanks in advance for your input.
 
celticnomad said:
430# on the tongue.

Even hauling water (240#) am I not better off taking it down to 500#-800# spring bars?
Click to expand...

Of course, that is why they have ratings on the bars.  That water weight may add little to the tongue weight depending where the tank is located.
 
I wouldn't sweat it too much. You can drop down a link or so on the chains to lighten the tension on the bars. The bars may not end up parallel to the frame, but as long as the correct amount of weight is being transferred back to the front axle, the WDH will still be doing what it is designed to do.
 
While the 600# spring bar would be a better match, the 800 is probably ok. The question is whether there is any tension on the bars when properly adjusted for the trailer and tow vehicle.

People sometimes lose track of the purpose of a WD hitch and the spring bars.  It is used to transfer tongue weight forward to the tow vehicle front axle and backward to the trailer axles.  The rating is the amount of weight it can transfer and does not necessarily have to equal the actual tongue weight. It just has to shift enough weight so that the tow vehicle axles aren't overloaded.  With a tongue weight in the 400-500 lb range, many tow vehicles won't even need a WD hitch. Many pick-up trucks, for example, are rated to carry 500 lbs directly on the hitch and have rear axle ratings capable of 2x or 3x that much.

Were those Cat Scale numbers done with the WD spring bars in place, or without? Ideally you should have both sets, but I'm guessing the ones shown were with the bars in place. The axle weights suggest to me that the bars should be adjusted to reduce the amount of weight transfer a bit, relieving the front axle and  increasing load on the rear axle.  That would typically mean loosening the bar chain (or bracket)one link (or bolt hole) to take a bit of pressure off.
 
Thanks all for your response.

Gary, to answer your questions, yes, the bars were in place. The numbers cited were the result of a re-weigh after I increased tension from the 4th to the 5th link from end. The SA went from 2860 to 2980,+120. The DA at 2880 went to 2720, -160. The trailer axle went from 3920 to 3980, +60.
The reason for going up a link was the way TV handled when loaded for trip, steering didn't feel connected to the road, it was a white knuckle ride to the scales. I did three weighs, TV and trailer, TV alone, TV and trailer again after adjustment taking me to the numbers in my post but TV seemed to go to other extreme, handled much better, could feel the road but the rig felt very rigid, very tight and getting so close to the SA rating was my concern.

Really surprised me how one link created such a difference in the feel of the truck.



 
Seems strange that a mere 120 lb extra on the steer axle would have that much effect, but I guess the proof is in the driver's hand on the wheel.  In any case, you amply demonstrated that the 800 lb bars are NOT overkill - you used some part of theirWD  capacity to change the weight distribution.  Probably not a large part, but as long as you can tighten or loosen the chain and get the weight shift you want, the bars are fine. If you were buying a new hitch, I would suggest the 600's, but you've already got the 800s and they are doing the job.
 
I note that the hitch weight is SLIGHTLY (10#) under the "magic" 10% number.  You may wish to shift a bit of weight forward and see if that helps the white knuckles.
 
Thanks Gary, really appreciate your input.

grashley, Yes I did that calc at the scales and noticed I was a shade under 10% while hoping for a 12%. Fresh water tank is in front of the axle so I'll be sending some H2O down that hatch. Good catch and thanks for reminding me.
 
I note that the hitch weight is SLIGHTLY (10#) under the "magic" 10% number. 
Click to expand...
You cannot reach that conclusion because the numbers given were with the WD springs bars already tensioned, thus shifting the tongue weight forward and backward.  The scale thus sees the portion of the tongue weight that falls on the rear axle, not the real total tongue weight.  You need the tongue weight for the trailer alone, without the WD.  celticnomad says he has that, but I don't see it in this thread.

Note that he added tension to the bars, thus reducing the part of the tongue weight that falls on the rear axle even more, yet the handling improved.
 
I was not suggesting that he did not have sufficient tongue wt, because of the reasons you mentioned, and I would not expect the scales to be that exact.  Since he was having some handling issues, increasing the tongue wt  MAY help address those issues.
 
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