check my wdh numbers please

[katoom400]

Just getting my new f250 setup with my Outback 250rs, previously I was pulling with a 2010 Tundra and the dealer had setup the hitch. The Ford is quite a bit taller than the Toyota so I had to drop the hitch to the lowest holes in the shank.

Here are my measurements:

Truck only

Front 41 1/2"
Rear 42 3/4"

Truck w/trailer and NO WD

Front 41 5/8" (only went up 1/8")
Rear 41 1/4" (dropped 1.5")

Truck w/trailer and WD

Front 41 1/2" (back to unloaded height
Rear 41 1/2" (1 1/4" sag)

in the following pics you can see it seems to sit pretty level, from the left side the trailer looks slightly nose down, but that could simply be the pavement it's sitting on.








you can see from the right side photo it actually looks a little nose high (both truck and trailer)

I only measure the truck on the left side, but now looking at these pics I should have measured both sides.

I'm not sure if I need to adjust the nuts that position the cam into the detents on the Reese Dual Cam setup since the hitch and the trailer are the same? only the truck changed. I was going to loosen the nuts and do a few figure 8's in the lot and then tighten them back up, but I didn't have a wrench big enough for those nuts (anyone know what size they are?)

Also I'm using 1200lb bars.

Moderator edit to re-size pictures to forum recommended limit of 640px maximum width.

[BarneyS]

Click here to find a CatScale near you or near whey you might be traveling next time out. Also, many junk yards, landscape material yards, and moving companies may have a scale that could weigh you.

I am not an engineer so don't know exactly what you should do for the lengthened drawbar. I think I would try one link more (6) under tension and see what happens. If that makes it worse, go back to 5. Just realize that that extension gives the trailer more leverage. You might be better putting it back in the other hole and just watching carefully how tight you jacknife the trailer when backing into a campsite.

As far as the slight push from passing vehicles, you will most likely always have some of that. I even get a bit of it with my Hensley but it does not require steering correction. Don't expect to eliminate that altogether.
Barney

[katoom400]

you are correct that I need to get it weighed, there just aren't any close scales to me. I'll have to see if I can find one on my next trip out.

so if I understand you correctly by moving the shank out ~ 1" it gives the trailer more leverage, therefore it takes less spring bar pressure to transfer the weight to the front axles. right now I have quite a bit of tilt on the head, should I try straightening that out a bit while staying on the same chain link (5)

I have the feeling if I bring the head angle back, I may find I need to lower the hitch head on the shank which means I'll need a longer drop shank.

[BarneyS]

katoom400 wrote:
Snip...

so on the way home I moved the hitch back 1 hole in the receiver which is roughly an inch. I figured the more clearance the better. On the ride home it felt like the trailer had more incluence on the truck than the ride there....Is it possible that moving the hitch ~ 1 inch is making that much of difference??

another thing I notice now looking at these pictures is that the trailer looks slight nose high in some of the pics..don't know if it's the camera angle, but maybe I'm a little light on the tongue at this point?

You bet it is possible that one inch is making a difference! It gives the trailer more leverage on the tow vehicle and is why it felt different on the way home. Nothing wrong with doing that though as long as you adjust the WD hitch to compensate. It probably threw off your WD a bit.

As far as the front being high and the tongue weight, you should adjust the attitude of the trailer by moving the hitch head up or down on the shank, not by changing the WD bar tension. Probably wouldn't hurt to add some weight to the front of the trailer if you can either. Looking again at your pictures, the rig looks pretty good just the way it is. I would leave it alone if it were me.

Have you weighed the trailer and truck to see what is going on? If not, that is the next step that I would do.
Barney

[katoom400]

well, I've pulled a number of times now and for the most part everything is good. something odd is that I feel a pit of push when cars pass me, but not big trucks? must have something to do with size and speed of the vehicle in relation to the air it pushes/pulls as it passes...but I don't remember that being the case with the Tundra.

also on my last trip, I was backing (jacking) into the site when my wife yelled "stop, you are touching the trailer with the truck", sure enough I was touching the trailer with the tail light lens...got lucky it didn't break.

so on the way home I moved the hitch back 1 hole in the receiver which is roughly an inch. I figured the more clearance the better. On the ride home it felt like the trailer had more incluence on the truck than the ride there....Is it possible that moving the hitch ~ 1 inch is making that much of difference??

another thing I notice now looking at these pictures is that the trailer looks slight nose high in some of the pics..don't know if it's the camera angle, but maybe I'm a little light on the tongue at this point?

[BarneyS]

Well, yes you are possibly correct but only a very tiny amount. You raise or lower the tongue by moving the hitch head up or down on the shank.

Changing the tilt of the head will affect the load on the WD bars which may lift or lower the hitch had a small amount. What is important is the amount of weight transfer that takes place and the attitude of the spring bars which also determines the number of links under tension for a given amount of WD.

You are on the right track and each adjustment affects the other so it is trial and error to get things right in most cases. 🙂

As I said earlier, if you are happy with the amount of weight transfer and have at least 5 links under tension then I would go camping! 🙂
Barney

[katoom400]

BarneyS wrote:
Actually, tilting the head up a bit will raise the tongue of the trailer not lower it.

If you are getting the weight distribution that you need and want, then I would SHUD.:) You need at least 5 links under tension so don't go less.
Barney

hmmm I though tilting the head back/down raised the tongue by putting more pressure on the spring bars given the same link setting?

[BarneyS]

Actually, tilting the head up a bit will raise the tongue of the trailer not lower it.

If you are getting the weight distribution that you need and want, then I would SHUD.:) You need at least 5 links under tension so don't go less.
Barney

[katoom400]

so I've been doing a little more thinking about how I can get my bars a bit more parallel with the frame.

since my head is tilted rearward it points the bars towards the ground at the same time putting more weight on the spring bars.

Currently I'm in the bottom holes on the shank, so I'm wondering if I straighten out the head angle, that would in effect lower the trailer, while bringing the bars more inline, that might allow me to raise the entire head 1 hole in the shank to get everything back to level...

the problem is titing the head back up towards the TV, will take tension off the spring bars. so I may have to go down 1 more link to get the numbers right...

that would put me in link #4

am I thinking about this correctly? or should I just leave the bars pointed down like they have been with my previous TV and just SUAD (shut up and drive!)

[katoom400]

not saying anyone is right or wrong...just looking for some clarification.

given ScottG's input, I can understand what he is saying about the angle that the cam sits in the detent. However this seems like it would not be possible with the head tilted back since it places the trunion bars at a tilted angle as well.

the only way I could see to getting the bars somewhat parallel would be to have the hitch head straight up, which may not be possible in every situation due to clearances.

I just called a rep at reese-hitches.com and was told the following:

ideally we would like the bars as close to parallel as possible be it round or trunion. We know this is not always possible, so as close to parrallel as you can get them while keeping safe clearances.

he also mentioned changing the ball height (not tilt angle) to allow the bars to be more parallel, however I'm not sure I'm understanding that part correctly?

in my mind the only way I can adjust the ball height would be a taller ball? I mean the ball mounts to the hitch head as do the trunion bars, so moving that up or down the shank should not change anything since it moving the trailer tongue along with it...or am I not thinking about that correctly?

in my situation I'm in the bottom holes on my shank to have the trailer level so not sure how I could even move it if that actually did change the angle of the trunion bars?

also, be it right or wrong they where always on the same angle on my dual cab longbed Tundra which was setup by the RV dealer, and I never experience any sway.....ever.....again not saying it was setup correct or incorrectly..I just never experienced any sway

[ScottG]

My info is not wrong and I can't help what someone else has posted.
I have set up a number of these, if you angle the bar enough the cam will easily slip out of the V - completely negating the effect and purpose of the cam system. It will still perform as a WDH but the sway control is rendered ineffective.
I've given my opinion and since this is starting to look like an argument, I'm going to let this thread go.
Feel free to use or ignore my suggestions and enjoy your travels.

Scott

[Need-A-Vacation]

ScottG wrote:
Look at the instructions, they will tell you the bars are to be parallel - and there's good reason for it.
Also look at the actual cam and how it fits into that upside down "V" in the spring bar. This is how the WDH keeps the trailer straight behind you. When the trailer moves away from straight behind the truck, that spring action of the cam climbing out of the V resists movement. When you have it at an angle it makes it too easy for the cam to come out of the V and you have diminished sway control. The steeper you have the bar, the easier it is for the cam to move out of the V. That defeats the "active" sway control.

Scott,

You are giving wrong info for a trunnion bar system!!! Round bars, yes, they should be close to parallel to the trailer frame or ever so slightly point down.

BUT a trunnion system is different. I have read the directions for a Reese system, and the numerous pages I linked in my last post which specifically deals with a DC system. Numerous post by some very knowledgable fellow members regarding the angle of the trunnion bars in relation to the frame to allow clearance of the trunnion lug so it doesn't hit the bottom of the trailer frame.

Here is a link to the instructions to a Reese Trunnion bar system, which gives a starting point with dimensions for the spring bar angle. NO WHERE does it state the bars should be parallel to the trailer frame. http://www.reeseprod.com/content/downloads/installation/N66022.pdf

[ScottG]

The forces on both sides are not equal because as the cam travels up the spring bar towards the hitch, the spring has to bend farther upward creating much more force to push the trailer back behind you. If the bar is level, the initial energy required to move the cam out of the V is much greater. If the bar is angled downward, the cam only has to move in a straight line to move out of the V. This initial tension is what keeps the trailer straight.

Yes, the bars are bent in an arc but they can be closer to parallel with the frame. This resits allowing the cam to travel up them and creates more tension to push the trailer back straight behind you.

[gijoecam]

Again, please explain how any part of the system knows whether it's level or parallel to any other thing. The bars are bent. It's geometrically impossible for them to be parallel to a straight frame rail.

Regarding your second point, look at the bar on BOTH sides of the cam, and both sides of the tongue. When making a turn, one cam moves forward, the other moves rearward. Yes, you are correct that the cam that moves to the rear is ramping up less of an incline. However, on the other side of the tongue, the bar is moving forward up a much steeper slope. Admittedly I haven't crunched the numbers, but I'd wager that the difference in correcting force between bars whose 'hook' on the contact point is more or less level compared to the force from bars with the angle seen in the OP's photo is pretty minimal.

I recall having a similar discussion here a couple months back... Someone found ONE manual somewhere which made a vague reference to the bars being parallel to the frame. (I think it was a round-bar from Blue-Ox, maybe?) None of the rest did, if my memory serves....

[ScottG]

Look at the instructions, they will tell you the bars are to be parallel - and there's good reason for it.
Also look at the actual cam and how it fits into that upside down "V" in the spring bar. This is how the WDH keeps the trailer straight behind you. When the trailer moves away from straight behind the truck, that spring action of the cam climbing out of the V resists movement. When you have it at an angle it makes it too easy for the cam to come out of the V and you have diminished sway control. The steeper you have the bar, the easier it is for the cam to move out of the V. That defeats the "active" sway control.