Good and Bad about Blue Ox Sway Pro

Well I decided against the Blue Ox Sway Pro since I finally understood how they felt the sway would be controlled. Other systems have the same and don't offer much sway resistance.

So I was researching the Equalizer brand. It seems a good alternative to the Reese Dual Cam HP system since they corrected the sliding arm bracket. I then found in the instructions that you couldn't use a traditional ball nut wrench. You had to use a 1 7/8" socket since the nut went into an enclosed area. The sockets are about $25 but they are 3/4" drive which is very very expensive. Since this size drive is in the hundreds, I thought about just using a 3/4" drive breaker bar. Luckily Sears had one where the head slides up and down on a round bar. It was $33. So just to put the ball on would cost $58 and that's with no torque spec!!!

Before I even planned to buy another hitch system, Blue Ox or Equalizer, I wanted to take apart my Reese Dual Cam system. I previously broke the head socket by the bar pushing against the cam lobe from an incorrect install. Then I found another problem after dealer sent tech to my home, to replace broke parts and reinstall. I found one of the cams was angled up, not allowing the bar indent to seat flat on the cam and get wedged into the gap between the cam and the cam pull up bracket. So I took it all apart to inspect. I thought I found a bent cam frame bracket.

Well took it all apart and neither of the cam frame brackets are welded perfectly square but I thought the one tab that bolted to the frame had bent.

I swapped the cams and now everything fit perfect.:h

Well I then put the cams back into their original frame brackets and now everything is square and perfectly aligned.:h

Thought maybe it was aligned because the force wasn't on the cam to push it out of alignment. Well, hooked it all up and pulled it about 50'. ALL IS GOOD!:B

The service tech somehow bolted it out of alignment but it's all good now. Very Strange but I'll take it.

I readjusted the cam on the bar indents and all is perfect now.

I may need to adjust the links, not sure. Even though my new 2012 F150 is supposedly the same truck as my 2010, the ride is a bit stiffer. Better suspension?? Or is it the lower profile 18" tires next to the 2010's 17" tire's tall side wall profile?? I'll see and if it needs, I'll adjust it on the go. Actually this parts pretty easy.

So I'm sticking with my Reese since it's working. Keeping my fingers crossed.

Following up on this - I have not received a response to two emails back to them. Site claims email reply within 3 hours which was the case when I got the canned response the first time. When I got more specific they have ignored me so far. I then placed two phone calls, 3 days apart (Mon and Wed). Both times the rep could not answer any of the specific questions that were brought up earlier. Both times the rep told me an engineer would be happy to call me back to explain how their sway control works vs. any other manufacturer with head tilt, angles of deflection needed between TV/TT, etc.

Still waiting on that call...

Bryan, the numbers Ron noodled is for a WD Hitch without the 'hook' on others
(cam follower)

Also, it is the whole system, not just the WD Hitch system.

First thing I've always done when asked to help. Is to check tongue weight
and levelness

How much force does a trunnion/round-bar with a 'hook' at the end where there
is a cam going to produce when it goes off center?

I'd venture to guess that trailer sway only involves a small degree of articulation between the TT and TV. Even the one time it happened to me with a trailer with negative tongue weight, just a couple degrees (if that) was enough to to start steering the van for me. (Luckily there was a pile of large rocks where I happened to pull over). Point is.... I don't think bar-load-changes do anything for sway.

I agree with all that Ben has said and will just expand on the following:

BenK wrote:
The amount of forces +/- is factored by the number of chain links, or more accurately how much the chain will allow the bar end to move or not move. The bar's preload will either increase or reduce...but am having problems with that, so see last sentence

I'll let you guys hypothesize the pound forces, both push and pull on
the tongue in reference to the center line

The following chart shows how bar-tip force varies as a function of TV/TT articulation.
The chart assumes each trunnion axis is offset 4" from the ball center and the A-frame included angle is 50 degrees.
Each trunnion axis is tilted at 15 degrees in a vertical plane which is parallel to the TV's longitudinal centerline.
Each bar is loaded to 1000# at zero articulation (TV and TT aligned straight ahead).



Next we need to consider how much the right bar tip moves "forward" relative to its chain suspension point and how much the left tip mores "rearward" when the TT swings left.
Assuming a 4" offset for each bar trunnion, 25-degree angle between A-frame and TT centerline, and 30" from ball center to chain suspension point --
if the TT swings 5 degrees left, the right bar tip will move forward a theoretical 0.337" and the left will move rearward 0.327".
If we assume the distance between bar tip and chain suspension point is 4" (about what it looks like in the Blue Ox videos),
each chain will be at an angle of about 5 degrees from its original assumed vertical orientation.

The load on the right bar has increased to 1025# and it will be pulling forward with a force of 86# on the right chain latch.
The load on the left bar has decreased to 968# and it will be pulling rearward with a force of 79# on the left chain latch.
So, the forces due to the inclined lift chains will tend to return the TT to zero articulation.

HOWEVER, if the WD bar trunnions were at zero tilt and assuming the same distance from bar tip to chain suspension point, the restoring force would be almost identical to (actually slightly greater than) the restoring force resulting from the tilted trunnions.
And, the difference in favor of the non-tilted trunnions will increase as the articulation increases.

So, if there is truth in the assertion that tilted trunnions will provide a measure of sway control which cannot be provided by zero-tilt trunnions, I think we have not yet found the reason.

Ron

The center of or axis of rotation are different for the tongue and
each bar. Their offsets are the distance from the ball's center line

The bar attachment to the tongue is fixed and there is compliance via
the chains. The center of that attachment is vague and needs noodling
but suffice to say it is within the chain latch assembly.

As the trailer goes off center line both bars will follow via their
attachment chain and rotation on 'their' center line

Since different center lines, those points (the attachment points on
the tongue and the bar chain attachment points) all three will swing
in an arc. The trailer moves towards the drivers side for this discussion

The passenger side will have the distance from the tongue attachment
point to bar axis of rotation increase

If the bar was fastened solidly on the tongue...it would NOT allow the
tongue to swing to the drivers side, but since attachment is via a chain,
the tongue is allowed to swing towards the drivers side

The other (drivers) side bar will reverse mirror that, as the
distance between the tongue fixation point to bar axis of rotation
will REDUCE

One bar is in tension and the other will be in compression...but they
are NOT straight, but bent

The amount of forces +/- is factored by the number of chain links,
or more accurately how much the chain will allow the bar end to move
or not move. The bar's preload will either increase or reduce...but
am having problems with that, so see last sentence

I'll let you guys hypothesize the pound forces, both push and pull on
the tongue in reference to the center line

This is part of how a WD Hitch System (traditional, non-Andersen)
sway controls. The change in bar loading is another...I think and back
to the last sentence. 'Think' in changing the WD'ing on the TV has
some effect, but not sure enough to post and get rocks tossed at me, again...



The part am having a tough time visualizing is the heat tilt and what
that does dynamically to the above {edit}...have understood how the
head tilt works for increasing the bar tension, but +/- distance and
resistance to off center tongue movements is only a few years old in
my old noggin... :B

I agree with Ron's post also and will be anxious to read what they have to say. This is what I have felt all along, and said so earlier in this thread back on Page 2, although not as complete as Ron's post. :W
Barney

Ron, I agree with what you said and have replied back to them again asking for specifics. We'll see what happens.

CHD Dad wrote:
If I follow your video, when the TT is not in a straight line the added tension on one side will help pull it back into line. Wouldn’t all designs do that? Second, how far out of line does the TT need to get on a typical 1000# hitch setup which seems the most common. Would the TT need to get several degrees or feet off center for physics to kick in on the bars to pull things straight? I thought I read that you got rid of the torque bolts to prevent “dog tracking” but other friction systems don’t seem to have that issue unless they are way too tight or on something like a snowy road.

Blue Ox Representative wrote:
Thank you for your interest in the Swaypro, we built caster into the trunions of the hitch head. This is what gives you the sway prevention and the friction sway control is not needed, it does not need to go off center for it to work, it is always working. This is similar to caster in a car, when going down the road the caster built into your front end keeps you straight going down the road and returns you to center when turning a corner. Blue Ox Swaypro is unique in the built in caster. I hope this answers your questions below. Please let me know if you have further questions.

I consider this to be a very disappointing response to your specific questions.

You asked, "Wouldn't all designs do that?" The response was, "we built caster into the trunions of the hitch head."
The only thing different about their hitch is the trunnion angle is not adjustable.
Other hitches can be set at similar tilt angles.
Does that mean they also have built-in caster and don't need any other sway-control mechanism?

The only parallel I can see with automobile front-suspension caster is that the automotive kingpin pivots on a axis which is "tilted" rearward at the top,
and the WD bar trunnion pivots on an axis which also is tilted rearward at the top.
But, the similarity ends there.

To have a "caster" effect, a wheel needs to be attached to the lower end of a kingpin so that the wheel's contact point with the pavement is behind the point at which the kingpin's axis intersects the pavement.

And, whatever effect the Blue Ox tilted trunnion has, it is not unique.

Ron

Ron, thanks for going over all my points. Definitely cleared some things up for me!

I also emailed them and received a quick reply. See below.

Thank you for your interest in the Swaypro, we built caster into the trunions of the hitch head. This is what gives you the sway prevention and the friction sway control is not needed, it does not need to go off center for it to work, it is always working. This is similar to caster in a car, when going down the road the caster built into your front end keeps you straight going down the road and returns you to center when turning a corner. Blue Ox Swaypro is unique in the built in caster. I hope this answers your questions below. Please let me know if you have further questions.

Thank you
Deanna
Blue Ox
 
Subject: SwayPro question
 
Hello – I am very interested in your Swaypro hitch.  My friend has the old design and loves it.  Never had a single issue and has towed thousands of miles with his rig.  The new design is intriguing but I fail to see how it controls sway with zero friction.  The old system had the bolts on the bottom to torque down similar to the Equal-i-zer.  The new system swings freely from side to side (I got to look at one in person).  I watched your computer simulation and understand what is being said, but how is your new design any different than any other hitch if you max out the head tilt of it?  Reese, EQ, Curt, etc. – just max out the head tilt and their geometry would be similar.  They all still have and need some sort of friction to control sway, be it an add on sway bar or built into the head/contact point or in the cam lobes.  Your tilt is extreme but it doesn’t look to be so much more extreme than what could be done on most other hitches.  Your chain capturing is unique and I like that quite a bit. 
 
If I follow your video, when the TT is not in a straight line the added tension on one side will help pull it back into line.  Wouldn’t all designs do that?  Second, how far out of line does the TT need to get on a typical 1000# hitch setup which seems the most common.  Would the TT need to get several degrees or feet off center for physics to kick in on the bars to pull things straight?  I thought I read that you got rid of the torque bolts to prevent “dog tracking” but other friction systems don’t seem to have that issue unless they are way too tight or on something like a snowy road.
 
I am sincerely interested in purchasing the hitch.  There are many pluses about it that I like but sway control is very important to me.