WDH set up help needed

I now have 1200 lb bars in place and they are a big improvement. Oddly, the bars are about a half inch longer or more. That means I can move the cam arm more toward the rear (of trailer). I can also make the bars more level since I don`t need to wind up the bars as tightly like I did on the old 800 lb bars to get enough wt. transfer

The Reese instructions I got with the WDH & DC package did not include the info. on dimension Y which gives the height of the end of the trunnion bar from the ground. That info. will also help.

With the new 1200 bars on, the handling is much better and there seems to be significantly less bounce in the rear of the trailer.

All appears to be good now!

myredracer wrote:
---Depending on how many links I have in the chain, I can't move the shaft far enough forward for the cams to sit correctly in the crook of the bars. Not sure why this is happening. The coupler is at the top of the A-frame so nothing unusual there. I may try moving the cam arm brackets forward slightly and I don't think there should be a problem with this.

The position of the frame plate depends on the depth of the frame rail. The 19 3/8" assumes a 6" depth.
The position of the frame plate also depends on the elevation of the rear end of the WD bar (determined by number of links under tension) when adjusted for normal use.

If the rear end of the bar is raised, the cam support arm needs to be shorter.
If the rear end is lowered, the arm needs to be longer.

The instructions state:
"The Measurements in figures 6, 6A, 7 & 7A are guidelines, adjustment of the cam arm length via the adjustment nut (Figure 5)
may be required after hookup in later instructions of this manual."

Ron

Thanks for the info. Ron

I got the 25/50/25% distribution from another RV forum. I agree with what you are saying. Our spring bars are undersized and I just received 1200 lb bars and will go through the setup procedure again. The weight distribution between axles should vary somewhat depending on the length of trailer and wheelbase of the TV and I think also the spring rates in the TV (ie, 1/2, 3/4 or 1 ton). I'm hoping that the 1200 lb bars will help reduce the bounce in the rear of our trailer.

I do seem to have one odd problem. Have set the cam arm brackets 19 3/8" as per the Reese instructions but the end of the threaded shaft is too close to the bolt on the bracket. Depending on how many links I have in the chain, I can't move the shaft far enough forward for the cams to sit correctly in the crook of the bars. Not sure why this is happening. The coupler is at the top of the A-frame so nothing unusual there. I may try moving the cam arm brackets forward slightly and I don't think there should be a problem with this.

myredracer wrote:
You ideally want 25% of the tongue weight transferred to the steer axle, 50% to the drive axle and 25% to the trailer axles. I can tell you that this is not easy. I have fiddled with the bar angle, number of links and ball height. I am currently okay on the steer axle but have too much on drive axle and not enough onto the trailer axles. It's important to get this a close as you can for handling and tire wear.

Can you tell us the source of this 25/50/25 "ideal" distribution of tongue weight?
If I correctly understand what you're saying, you're trying to achieve something which is physically impossible.
Perhaps that's why you're having so much trouble getting the distribution you want.

Depending on TV and TT dimensions, a 1000# tongue weight might cause a load of 400# to be removed from the steer axle and a load of 1400# to be added to the drive axle.

For your 2009 F-250, Ford specifies that the steer axle should be returned approximately to its unhitched load.
This means that a load of approximately 200# would have to be transferred to the TT's axles.
That 200# load, in turn, would cause about 400# to be added to the steer axle and 600# to be removed from the TV's drive axle.

Net resulting axle loads would be:
steer axle = 400# removed by TW plus 400# added by load transfer = 0# net change
drive axle = 1400# added by TW minus 600# removed by load transfer = 800# net increase
TT axles = 200# added by load transfer

The approximate net load changes for the assumed 1000% tongue weight are: steer/drive/TT = 0#/800#/200# = 0%/80%/20%.

Other approximate distributions (again depending on TV/TT dimensions) are: 10/65/25, 20/50/30, and 30/35/35.

The load transfers to the steer and drive axles are uniquely determined by the amount of load transfer to the TT axles.

Ron

We recently bought a Reese dual cam WDH for our new 29' TT with scaled weight of 6600 lbs. I have been struggling to get it all dialed in correctly. So far, I have learned that measuring the heights of the fenders before and after does not give an accurate picture of the weights that are being transferred. You may *think* it's set up okay if your front fender height settles back down to where it should be, but you won't know if weight is being transferred correctly to the drive axle and trailer axles.

You ideally want 25% of the tongue weight transferred to the steer axle, 50% to the drive axle and 25% to the trailer axles. I can tell you that this is not easy. I have fiddled with the bar angle, number of links and ball height. I am currently okay on the steer axle but have too much on drive axle and not enough onto the trailer axles. It's important to get this a close as you can for handling and tire wear.

In the case of our new trailer, the tongue weight is almost double what the factory dry hitch weight is and the TT actual weight is 6600 vs 5200 dry weight. And we haven't even got much loaded in the trailer. We have only 200 lbs left before we reach the TT GVWR. I had ordered 800 lb trunnion bars in advance of getting our new TT thinking that this would be well above the actual tongue weight with TT loaded. Now I am looking at upgrading to 1200 lb bars to be able to get the WDH adjusted properly. I would never have known if I hadn't spent the time at a scale. I also have a feeling that the undersized bars are resulting in more rear end bounce than I'd like (cupboards fly open while travelling).

Dry weights in trailers are useless to go by and same with some TV data like payload capacity on the door jamb sticker and curb weight.

You (OP) have not posted info. on your trailer (dry weights and length) or on your TV so it's hard to give any good feedback. Until you get to a scale, you are simply flying blind and wasting much of your time. You would do a lot better to get the hitch set up as best as you can and head to a scale. You need 3 passes to get the data you need. You may need to visit the scale several times before you are done or have to spend a lot of hours unhooking the trailer, making adjustments and going around for another pass(es). And what bar size do you have? If you need info. or help related to going to a scale, just say so. :)

OP,

The tilt is mainly used to transfer weight to the front wheels. The shank height is used to match the height of the trailer tongue when it is level. You can add another chain link in order to keep the bars level.

Chaos wrote:
The TV measurements look good to me but the trailer is too high in front by 5/8 or so. If I drop the head to the bottom hole, then I don't have enough tilt adjustment to get the ends of the spring bars to the correct height according to the hitch instructions. So now what?

I have another hole I can drop on my current shank. I am out of tilt on the head. Reese says my spring bar ends should be 9.5 inches from the ground. If I drop down to the bottom hole, I can not get 9.5 inches of clearance.

I cannot reduce the tilt of the head as it is already fully forward (toward the TV).

If 1) the head is fully forward and
2) you can't lower the ball mount to eliminate the TT's nose-up attitude without violating the 9.5" "clearance specification", then
3) there obviously is something wrong with the "clearance specification".

If it's okay for other other COUPLER HEIGHT and COUPLER STYLE combintions to have "SPRING BAR HEIGHT (Y)" values as low as 4.5", I see no reason for you to have to stick with the 9.5" value.

Forget about the 9.5",
drop the ball mount to get the tongue level or below level,
and then reduce the number of links between u-bolt and hook as needed to get desired load transfer.

IMO, you're placing far too much emphasis on the 9.5" "specification".

Ron

I should have looked at the Reese installation manual. Sorry if I added to the confusion. I was wondering how they would know if the trailer had flipped axles for instance, but they must have it covered.

My comments in blue this time

Chaos wrote:

BenK wrote:
The OP is bit ahead in the process

Need or suggest to understand the 'goal' of it all...including weights vs ratings

Decide if you believe in the ratings or not

I will be following all the ratings, as required by law.

Good for you and a rare position/understanding on this forum

If not, then do whatever but note that over the ratings may have warranty denied...if
they find out

If yes, then go out and weigh the whole setup. Axle by Axle both fully loaded
and empty

I can't do that until I get the hitch set up. Can't tow it anywhere without a hitch.

Why would empty weights matter at all? I will never run it empty.

Then use that trailers GVWR (Gross Vehicle Weight Rating) as the
max or guesstimate how much it will weigh fully loaded....note that
the 'dry' is useless. As it is the stripper model and most do NOT
purchase a stripper model. So it *WILL* weigh more than the 'dry'
weight

Empty weights vs it's ratings tell how much 'capacity' you have
for all the stuff loaded on and in it

Read up on the HOW2's and understand them

I have been reading and I'm doing my best.

The OP is adjusting without knowing where they are in reference to their ratings
and unknown to us is the orientation of the setup

What do you mean "the orientation of the setup?"

How level the trailer is in reference to the ground. Why it is best
to setup on level ground, like a parking lot

Old rule of thumb is to also have the TV evenly drop, but that is no
longer the OEM's advice. It has to do mainly with oversteering tendencies
when too much is removed from the TV's rear axle over to the TV's front axle

Now it is to move enough to the front to maintain enough traction
for steering and controlling the setup

I like to have the trailer level at it's highest pointing and preference to
have it pointing slightly down

I do not comprehend. At all.

Reference above and is that the trailer is level with the groung.

If it is pointing higher than 'level', many have instability (sway
is the main issue) with the trailer

Moving the shank/head without knowing the orientation is useless

Tilting the head is a ditto and note that tilting the head is to gain more
WD spring bar (either round or trunnion) distance to increase their preload
Tilting it back towards the trailer is the right way. Tilting it forward removes
WD spring bar preload potential

The height of the shank/head is determined by the final orientation of the
trailer and the TV

The front end height as instructed by the manual is out of context without
knowing the weights, the spring bar ratings, etc

OP, please post these ratings and actual weights: front GAWR/GWR, rear GAWR/GWR,
GVWR and the actual weight of the trailer. The trailer dry weight is not helpful,
but it does provide a range of the tongue weight vs the actual weight

Again, I cannot take it to a scale to get the weights until the hitch is set up. I am using the tape measure method, as instructed by the hitch and vehicle manufacturers. I could post my ratings, but they would not provide any useful information.

Once I get everything set up, I do plan to take it to the scales.

Since you can not move it, then setup where ever you have it and get
it as close to 'level' to the ground as possible. Then go to a very large,
level parking lot to fine tune it AFTER you go out and weigh the
whole setup axle by axle

Both to confirm you have it under the ratings and if the WD bars
are sized correctly for that tongue weight (a WD Hitch system can
be undersized, over sized to just right (there is a range each set
of bar ratings will cover

Finally...hope you either understand this or have seen and understand
how the ratings system works. This is a diagram showing how it works
in graphical form

Note that the MTWR (max tow weight rating) is based on a 'curb' TV,
which is the stripper model. Unless you have a stripper model...it WILL
weigh more and will have a pound for pound reduction in that MTWR...also
anything you load on/in the TV will also reduce the MTWR pound for pound

howmuchcanitow

TomG2 wrote:
I suspect that the 9.5 inches is what is causing the problem. How could Reese know if you have a lifted truck, extra tall trailer, over or under the frame hitch? No-way, unless you told them.

A lifted truck would not change the 9.5 inches. It may cause you to need a shank with a longer drop. It does not change the needed height of the ball, since that is determined by the trailer.

As far as the trailer height and coupler style (over vs under), Reese has accounted for that. There is a chart in the instructions, and you look up your frame height and coupler style, and that chart says for my trailer, I need 9.5 inches.