Vehicle Sway Control Vs WDH

[Fender]

In looking at new vehicles I see that some come with towing sway control. I'm wondering how this compares to a WDH with sway control?
Would it mean that a WDH without sway control would suffice?

[cpaharley2008]

Most WDH, by nature, help reduce sway! Any tightening of the connection between the tow and trailer would help with sway control!

[Centex]

IMO the best bet is to prevent a trailer from trying to initiate sway, that is, eliminate its inherent propensity to sway.

That's accomplished by ensuring adequate tongue weight (10% of loaded trailer weight on the tongue minimum, more tongue-weight-bias inherently further decreases a trailer's propensity to sway). That's the 'passive' tongue weight (measured without the WDH engaged). A trailer with proper weight-bias is inherently stable and resists sway even in the face of external forces like passing big-rigs, etc.

A 'plain' WDH can then be used to correct for whatever 'sag' is imposed by the tongue-weight on the tow-vehicle (and give a generally better overall-rig ride characteristic in many cases).

All other measures (friction anti-sway bar, cam-type anti-sway devices, 'Hensley' types, and vehicle stability control) do nothing to reduce/improve a poorly weight-biased trailer's inherent propensity to sway, they only 'fight' and/or try to mitigate that inherent propensity if it is present.

IOW, eliminate the potential problem at its root source, then all other add-ons become unnecessary / redundant / never come into play.

One opinion, just for your consideration, happy trailering!

[Ron in BC]

Originally Posted by Centex

IOW, eliminate the potential problem at its root source, then all other add-ons become unnecessary / redundant / never come into play.

One opinion, just for your consideration, happy trailering!

Nope, make that two opinions.

Ron

[bborzell]

To your point of the relative benefit of a WDH as compared to built in sway control, pretty much every built in sway control I have either owned or read about does nothing to keep sway from becoming induced by any of the factors that have already been mentioned.

The factory anti sway system simply senses the forces applied to the receiver that accompany sway (already underway) and applies the trailer brakes in a manner that is similar to the action that your brake controller manufacturer wants you to take by using the manual trailer brake slider when you detect sway (by applying the trailer brakes without applying the tow vehicle brakes).

To further complicate matters, I have read vehicle instructions that suggest that using a WDH with a factory anti sway option could result in one or the other system not working optimally.

After thinking about this possibility for much longer than it is probably worth, I am guessing that the reason for this ”caution” comes from predictable liability butt covering that might be grounded in an assumption that most WDHs would inhibit the forces that would tell the vehicle anti sway system to apply the trailer brakes when sway might have otherwise been detected.

Then again, if the WDH reduces the forces to the receiver, it might be doing so while in the act of controlling any beginning sway. It’s amazing what can be accomplished when nobody cares who gets the credit.

[Fender]

Originally Posted by bborzell

To further complicate matters, I have read vehicle instructions that suggest that using a WDH with a factory anti sway option could result in one or the other system not working optimally.

Hmmm. That's a good point that I hadn't considered. If you have both (vehicle sway control & WDH sway control) chances are there could be a conflict.
I'm assuming, but don't know for certain, that vehicle sway control is a selectable option, ie can be turned off.

[Centex]

Originally Posted by Fender

I'm assuming, but don't know for certain, that vehicle sway control is a selectable option, ie can be turned off.

Yes, but why would you want a trailer system recommending one to disable a feature that could help maintain vehicle control (not all adverse situations originate with a trailer)?

[bborzell]

Originally Posted by Fender

Hmmm. That's a good point that I hadn't considered. If you have both (vehicle sway control & WDH sway control) chances are there could be a conflict.
I'm assuming, but don't know for certain, that vehicle sway control is a selectable option, ie can be turned off.

It was not an on/off feature on my 2014 Jeep Grand Cherokee Overland.

And I have not stumbled upon an off switch on my ‘22 1500 RAM Laramie.

[Brian B-P]

Originally Posted by bborzell

To further complicate matters, I have read vehicle instructions that suggest that using a WDH with a factory anti sway option could result in one or the other system not working optimally.

The frictional damping of typical hitch system sway control feature may make the tuning of the vehicle's anti-sway control system less optimal, but wouldn't fundamentally change it. The action of a vehicle's anti-sway system certainly won't reduce the effect (or effectiveness) of the hitch system's damping.

I wouldn't worry about it, but I would also avoid weird systems with springs and cams always trying to force the trailer to be straight in line with the tow vehicle.

[Brian B-P]

Originally Posted by Centex

IMO the best bet is to prevent a trailer from trying to initiate sway, that is, eliminate its inherent propensity to sway.

I agree, but it can only be eliminated within a limited speed range.

Trailer stability is affected by many factors, including speed. No trailer is inherently stable at all speeds, and every trailer is less stable with increasing speed. The trick is to make sure that the speed at which the trailer becomes marginally stable is comfortably above the highest speed of travel.

Originally Posted by Centex

That's accomplished by ensuring adequate tongue weight (10% of loaded trailer weight on the tongue minimum, more tongue-weight-bias inherently further decreases a trailer's propensity to sway). That's the 'passive' tongue weight (measured without the WDH engaged). A trailer with proper weight-bias is inherently stable and resists sway even in the face of external forces like passing big-rigs, etc.

True, except that - as already noted - no tongue weight will create inherent stability at all speeds. The obsessive attention on tongue weight fraction while completely ignoring other factors leads to poorly set up trailers which are much less stable than they could be.

Originally Posted by Centex

All other measures (friction anti-sway bar, cam-type anti-sway devices, 'Hensley' types, and vehicle stability control) do nothing to reduce/improve a poorly weight-biased trailer's inherent propensity to sway, they only 'fight' and/or try to mitigate that inherent propensity if it is present.

That's not true. Sway is inadequately damped oscillation, and damping is a very important part of that. Damping results from various sources, including tire characteristics, suspension damping... and hitch friction. At the same time, I agree that suitable stability is certainly possible (and commonly experienced) with the very low hitch friction of a simple weight-carrying ball hitch.

The trailer will be moved out of alignment with the tow vehicle, whether due to going around a corner or due to being pushed by some external force. Stability is all about how the tow vehicle and trailer system responds to that: if the trailer swings side-to-side in increasing motions it's unstable, if it keeps swinging the same amount it is marginally stable, and if (as they should) the motions quickly die out it is stable.

[Mike G]

Originally Posted by bborzell

...The factory anti sway system simply senses the forces applied to the receiver that accompany sway (already underway) and applies the trailer brakes in a manner that is similar to the action that your brake controller manufacturer wants you to take by using the manual trailer brake slider when you detect sway (by applying the trailer brakes without applying the tow vehicle brakes)...

Are you certain the vehicle's factory systems apply brakes to the trailer? I thought they only apply brakes to one side or the other of the tow vehicle, although perhaps I've been left behind by recent advances.


To the OP: I would consider a hitch with built-in sway control, or even a simple add-on sway bar, to be considerably superior to anything built into the tow vehicle. We're talking about mechanical friction at the conjunction between tug and trailer versus a computer that assumes it knows what is happening even though it has no idea how much mass and force your trailer is exerting.

[Centex]

Just FYI attached is the 2022 Ford F150 Owners Manual section describing "How Does Trailer Sway Control Work". This for F150s with the Ford integral trailer brake controller.

Note the statement "The system applies the brakes to the individual wheels and reduces engine torque to aid vehicle stability." Obviously, the system cannot apply brakes differentially to each wheel on a trailer (they all have a single common control feed via the 7-pin connector), but it is likely that since different vehicle wheels get different braking applications the trailer brakes are applied different from at least some of the vehicle wheels at any given instant. It's not stated if that's employing some algorithm more sophisticated than the accelerometer control common to aftermarket TBCs.

BTW, note that the Trailer Sway Control can be toggled Off (separate from the vehicle's own Stability Control System which can also be toggled Off).

Finally, reviewing the section in this F150 Manual about use of a WDH, I find no suggestion or caution that use of a WDH should alter the normal use of either the Vehicle Stability Control system or the Trailer Sway Control system. I find no mention or caution whatsoever about the use of hitch-mounted or other 'add-on' trailer anti-sway devices.

Other vehicles may of course have completely different systems and operating strategies / guidance.

[MrLynn]

I notice that the Escape19 Configuration Options lists three optional hitches. These replace I assume a simple ball-mount hitch:

e2 by Fastway Integrated Sway Control and Weight Distribution Hitch +$ 730.00
Equalize Hitch (Pro-Series 600lb Trunnion) +$ 385.00
Equalize Hitch (Pro-Series 600lb Trunnion) with Sway Control Bar +$ 490.00

Like many customers, I know nothing about these alternatives.

Assuming your E19 is more or less stock, and you are planning to tow with an adequate vehicle (e.g. Ford F150), why would you choose one of these over the basic ball mount, if as Alan E. says, as long as your hitch weight is adequate (10-15% most say, assuming you have some way of determining that) they are unnecessary? And why would Escape be offering them?

[JeffreyG]

Originally Posted by Centex

Just FYI attached is the 2022 Ford F150 Owners Manual section describing "How Does Trailer Sway Control Work". This for F150s with the Ford integral trailer brake controller.

Note the statement "The system applies the brakes to the individual wheels and reduces engine torque to aid vehicle stability." Obviously, the system cannot apply brakes differentially to each wheel on a trailer (they all have a single common control feed via the 7-pin connector), but it is likely that since different vehicle wheels get different braking applications the trailer brakes are applied different from at least some of the vehicle wheels at any given instant. It's not stated if that's employing some algorithm more sophisticated than the accelerometer control common to aftermarket TBCs.

BTW, note that the Trailer Sway Control can be toggled Off (separate from the vehicle's own Stability Control System which can also be toggled Off).

Finally, reviewing the section in this F150 Manual about use of a WDH, I find no suggestion or caution that use of a WDH should alter the normal use of either the Vehicle Stability Control system or the Trailer Sway Control system. I find no mention or caution whatsoever about the use of hitch-mounted or other 'add-on' trailer anti-sway devices.

Other vehicles may of course have completely different systems and operating strategies / guidance.

I certainly would not want my tow vehicle regularly applying one or more brakes to damp out sway while I'm driving along steady at a high speed. That's not going to be good for fuel consumption and brake wear. I'm OK with the sway control as a backup to the backup kind of thing, but I would not want it as the main step (following proper loading) to damp out sway in my trailer.


So I'd put it out of mind in terms of selecting my hitch. If I was inclined to run a WDH + sway control system for my trailer in a vehicle that didn't have an active sway system, then I'd continue to do so in a vehicle with it.

[Fender]

Wow! Great info - thanks everyone. Though I'm not sure I understand it all!

[JeffreyG]

Originally Posted by Brian B-P

I agree, but it can only be eliminated within a limited speed range.

Trailer stability is affected by many factors, including speed. No trailer is inherently stable at all speeds, and every trailer is less stable with increasing speed. The trick is to make sure that the speed at which the trailer becomes marginally stable is comfortably above the highest speed of travel.

Everything Brian B-P said is correct. I have experience towing my BIL's expedition trailer. This trailer is very sensitive to loading, we know we have to put the heavy gear to the front and keep the boats shifted forward. But there is a limit to boat placement to avoid hitting the car in a turn.


The trailer will be stable up to some speed, and then it will develop a persistent sway. Go faster and I'm sure it would be a disaster. And we can directly shift what wiggle speed by how the trailer is loaded.

[oldwave]

Pro pride and Hensley seem to be the best wdh and sway control, that said they are very expensive. I ordered one.

[Perry Butler]

Originally Posted by bborzell

It was not an on/off feature on my 2014 Jeep Grand Cherokee Overland.

And I have not stumbled upon an off switch on my ‘22 1500 RAM Laramie.

We pulled a Cougar 25', Lance 23' and a 25' Bigfoot with our 2015 F150, and had to remember to turn off the F150's sway control every time we started the truck. Yeah, right!

Our Cougar had an Andersen WDH and went into a sway situation when Terry was driving. Luckily I quickly squeezed the trailer brakes. Terry refused to drive with the Andersen hitch attached ever again. Both the F150's built-in sway control and Andersen's supposed sway control failed! And yes, the Andersen was set up correctly, but when I talked to Andersen they admitted it worked better with trailers lighter than the 6,000# Cougar.

When we purchased the Bigfoot we purchased a Blue Ox Sway Pro hitch. Easiest WDH to hook up we've ever owned and it leveled the camper easily (don't need to play the shim game). Also had the Blue Ox for the brief time we owned the Lance (one trip to the west coast was enough for us). Neither the 2015 or the 2019 F150's ever applied the brakes just going down the road.

Our 2019 F150 also turns on the F150's sway control by default every time we start the truck, but we're now pulling the Escape 5.0 5th wheel, so no issues.

Enjoy,

Perry

[Mike G]

Originally Posted by MrLynn

I notice that the Escape19 Configuration Options lists three optional hitches. These replace I assume a simple ball-mount hitch:



Like many customers, I know nothing about these alternatives.

Assuming your E19 is more or less stock, and you are planning to tow with an adequate vehicle (e.g. Ford F150), why would you choose one of these over the basic ball mount, if as Alan E. says, as long as your hitch weight is adequate (10-15% most say, assuming you have some way of determining that) they are unnecessary? And why would Escape be offering them?

A number of possible reasons exist for any given trailer owner to want one or another.

All of them will help level the rig (assuming one doesn't have air suspension). All of them will smooth the ride comfort, damping the tendency of the trailer tongue to porpoise up & down on the ball and jiggle the tow vehicle with its occupants.

The Fastway from Progress Mfg has friction where the square bars contact the L brackets (which are mounted on the trailer frame), and this friction discourages changes in angle between the tug and TT. (Progress Mfg also makes the Equal-i-zer hitch with 4 points of friction, btw; I've had one and they are good.)

I think the other WD hitches you've listed do not have any such friction points, but the chain linkages attached to the trailer frame do have a similar (albeit much smaller) effect on angle changes. They can, however, be used in conjunction with an add-on, flat "friction sway bar" if desired (that's #3 on your list); these bars often must be loosened before backing up to avoid bending them, and when wet they lose efficacy & so must be tightened further (rainy weather).

Some people will choose sway control for peace of mind, as a sort of fail-safe, even if they have proper tongue weight. Some will be towing with a short-wheelbase SUV, which is not optimal for keeping the "tail" from "wagging the dog." Some will be towing a behemoth TT, 30+ feet long, which is quite the "tail"! Some will want WD for leveling or ride comfort and think, why not have a WD hitch that controls sway as well? There may be other rationales besides these.

Personally, I don't plan to use anything but a ball mount with my Lexus GX470 (equipped with air suspension) when I get my 17B. If I were buying a 19' (really 20' long) I would think about it; if I were getting a 21' or 23' I definitely would have sway control. The GX's wheelbase is rather short. In 2005 I bought a 23' TT and towed it with a 2000 Mercury Mountaineer (twin to Explorer, remember the Firestone blowouts/rollovers?) short wheelbase SUV and that TT felt mighty unsteady without the Equal-i-zer hitch; with that hitch it felt steady and secure even when the 18-wheelers blew by me. Later on, towing a 17' stick TT with a 2008 Highlander, I never had any issues beyond comfort but I did finally buy an Anderson No-Sway to smooth the ride for my wife's sake, and I liked it quite well. Neither the Anderson nor the Equal-i-zer were complex to install, either; a tape measure, hand tools, and an hour of working thoughtfully did it.

My suggestion: these hitches are for sale all over the place, and one can choose from a greater variety of hitches at better prices than Escape's offerings.

[huskersteffy]

Ever towed your trailer on a hot summer day along a flat, midwestern two-lane road with a 30+ MPH cross wind and then have a big 'ole semi blow by you in the other direction?

First, its as if someone flipped a switch and turned off the cross wind. Then a huge suction force as the rear of the semi passes by (Bernoulli equation!). Finally, someone flips the cross wind "ON" switch again.

You will be most glad you have a WDH with anti-sway.