Homemade Friction Sway-Straight Tongue

F7arcticcat

Well-known member
Nov 26, 2007
499
55
28
West fargo, ND
I have wanted to add an anti sway device but couldn't find anything for a straight tongue trailer that many of us have. I decided to make my own. I have a 7x31 Legend Trailer. It pulls really nice up to about a 18-20mph wind, then I can tell its back there. I am pulling it with a 2019 F250 gas. All of the reviews for these simple sway control units are very good so I thought I would give it a shot.

The total cost of the steel and 2 Kurt's Friction control units was about $130 (cheap!!!). The plates that mount to the trailer are 6x6 and 1/4 inch steel (trailer tongue is 6 inches long by 3 wide). The tubing is 2x2 by 1/4 inch. The longest part of the tubing is 12 inches. I used 1/2 bolts to mount the plates to the trailer and 3/8 for the sway control ball plate. The kit comes with self tapping screws but I used bolts instead. It clears the jack no problem so I probably would have been fine at 10-11 inches. I still have plenty of clearance for the door as well. I drilled all my holes before welding things together.
They recommend one anti sway on each side if you are over 6,000 lbs and 26 feet. I am right at 6,000 lbs and 31ft. If I was going to do just one, 4 or 5 inches from the trailer frame would be plenty. The distance from both balls on the anti sway should be 24 inches. I ended up at 25 inches because of where the jack sits. I did a few tight turn and everything seems ok.
I haven't got it on the road yet so no reviews there, but overall happy with the way it turned out.
 

Attachments

volcano buster

Well-known member
Nov 26, 2007
3,511
1,016
113
Stayton Oregon
Have you towed that trailer with your 2019 F series in windy conditions before installing this device?

If I were to believe the Ford marketing campaign, the pickup should detect a lot of the sway from the trailer and respond with its braking algorithm to help correct the sway.

Just curious if they two systems would mask each others contribution.
 

SODAK-DOO

Premium Member
Premium Member
Dec 3, 2015
173
42
28
eastern south dakota
did you just go off their recommendations for the decision for 2 of them? Or do you have past experience with them to know? i have a 7.5' x 29' mission enclosed that i just ordered one for but could be talked into two being they are only $45 for a kit that includes the weld on piece for your ball hitch.
 

F7arcticcat

Well-known member
Nov 26, 2007
499
55
28
West fargo, ND
The electronic sway control does nothing unless it is swaying violating. I have never felt it kick in. My F150 had the same thing and never felt it on that pickup either.

I was originally going to do one because I thought the jack was in the way. After I came up with this I decided to try two right away. It was easier setting two up at the same time compared to coming back later and doing the other side. I was also thinking two would put less pressure on the trailer hitch and apply the pressure more evenly.

You can adjust the pressure which I plan to start light. The trailer hitch that connects to the tongue has 3 bolts running through it from the factory in less surface area than this. This tongue at 3x6 is way more stout than some I've seen. The aluminum is fairly thick as well. Hopefully I'm not eating my words down the road.:)
 

meathooker

Well-known member
Jan 4, 2008
1,471
419
83
Boise, ID
that is a lot of side loading on that tongue.

I'd consider putting another tube back 45deg with another plate to help lower the stress in that area.
 

turbolover

Enduring the heat till Braap Season
Staff member
Jul 4, 2001
3,646
2,323
113
Rigby, Idaho
Interesting setup. I'd keep an eye on the tongue, that's a lot of leverage and holes, IMHO.
That was my thought also. I would definitely keep and eye on this area for cracking and any unusual deforming from the side loading.
 

Coldfinger

Well-known member
Nov 26, 2007
2,040
372
83
Nebraska
Should a person be concerned about tongue strength after drilling 4 holes through it? The vertical strength is probably of more concern than horizontal because I doubt there is that much torque required to prevent sway.

Vertical strength may not be a concern (with 4 additional holes) until your trailer weight nears the max. I doubt they made the tongue in those dimensions unless they felt it necessary to safely carry a load for which the trailer is rated, and each hole drilled weakens the tongue.

Look at it this way - how many holes can be drilled before the tongue strength is significantly compromised? Somewhere between 1 hole and 12 holes in the same general area? Doubtful anyone would drill 12 holes and not be concerned about failure. Doubtful anyone would be concerned about drilling 1 hole (except maybe the design engineer, if they have one). The concern increases with each additional hole but it is anyone's guess (engineers excluded) when the number of holes drilled will significantly compromise the tongue integrity.
 

F7arcticcat

Well-known member
Nov 26, 2007
499
55
28
West fargo, ND
The hitch is held on by 3 -1/2 bolts that is in less area that the plates I added. This has to hold 600 to 800 lbs of tongue weight. If the tongue wasn't as heavy duty has it is I probably would not have attempted this. I'm no engineer though!!
I've put on about 50 miles in. 25mph wind and it was much more stable.
 
Last edited:

turbolover

Enduring the heat till Braap Season
Staff member
Jul 4, 2001
3,646
2,323
113
Rigby, Idaho
The hitch is held on by 3 -1/2 bolts that is in less area that the plates I added. This has to hold 600 to 800 lbs of tongue weight. If the tongue wasn't as heavy duty has it is I probably would not have attempted this. I'm no engineer though!!
I've put on about 50 miles in. 25mph wind and it was much more stable.
I am not digging on you for coming up with an idea. I am just sharing a concern. I would keep an eye on that area to see if it starts to do anything funky because of your mod.
I hope it all works out great for you and gives you miles of troublefree towing. However any time you make a modification like that to the tongue or frame, I would closely monitor it to see if it introduces any strange undesired effects.

Please report back to us and give us an update on your observations after the first trip and after a year or two.
 

MNBlizzard

Well-known member
Feb 28, 2012
190
58
28
Duluth, MN
Interesting setup and the same thought has definitely crossed my mind on my 1000mi one-way trips out West. I wonder how much force is actually being place on the tongue with the sway bars, but I believe it has to be quite a bit to move a 5000# truck and a loaded 3500# trailer around going down the road. That sort of math is way above my pay grade. I have found that when my 23' enclosed starts pulling tough or swaying behind my F150, it is time to slow down and enjoy the scenery a bit more.

In my opinion, if the sled trailer manufacturers thought a sway bar was needed, they would incorporate it into their designs like RV trailers. That being said, I don't doubt that the added sway bar setup you have will strong arm the trailer and make a more compliant pull. I wonder if in lieu of drilling thru the tongue, you would of been better by sandwiching the tongue with oversized mounting plates.

As it is though, I'd be concerned with the added stress/load in the tongue as other mentioned along with galvanic corrosion. IMHO, the 3 coupler bolts have more of a vertical load/stress and the very design of the tubular tongue is built for it. The new sway set up will add a horizontal stress in an area that I imagine was not designed to have it there, nor drilled thru, and the result has to be weaken strength in that area; if of any consequence is one unknown to us here. I'd think of it more along the lines of a 2x4; it is stronger on edge than laying down. The sway bars will be putting stress on the 4" side of the 2x4 where as the coupler is on the 2" strength side.

Definitely give us all an update after next season.
 

F7arcticcat

Well-known member
Nov 26, 2007
499
55
28
West fargo, ND
It has crossed by mind to weld an aluminum bar across the top and bottom for added strength. As for corrosion, I did put a thin plastic liner between the aluminum and steel plate, if that is what you are referring to.


Interesting setup and the same thought has definitely crossed my mind on my 1000mi one-way trips out West. I wonder how much force is actually being place on the tongue with the sway bars, but I believe it has to be quite a bit to move a 5000# truck and a loaded 3500# trailer around going down the road. That sort of math is way above my pay grade. I have found that when my 23' enclosed starts pulling tough or swaying behind my F150, it is time to slow down and enjoy the scenery a bit more.

In my opinion, if the sled trailer manufacturers thought a sway bar was needed, they would incorporate it into their designs like RV trailers. That being said, I don't doubt that the added sway bar setup you have will strong arm the trailer and make a more compliant pull. I wonder if in lieu of drilling thru the tongue, you would of been better by sandwiching the tongue with oversized mounting plates.

As it is though, I'd be concerned with the added stress/load in the tongue as other mentioned along with galvanic corrosion. IMHO, the 3 coupler bolts have more of a vertical load/stress and the very design of the tubular tongue is built for it. The new sway set up will add a horizontal stress in an area that I imagine was not designed to have it there, nor drilled thru, and the result has to be weaken strength in that area; if of any consequence is one unknown to us here. I'd think of it more along the lines of a 2x4; it is stronger on edge than laying down. The sway bars will be putting stress on the 4" side of the 2x4 where as the coupler is on the 2" strength side.

Definitely give us all an update after next season.
 

Betterview

Well-known member
Mar 16, 2008
182
58
28
69
Central Minnesota
A 31 foot aluminum trailer behind a 3/4 ton pickup should not ever sway. Something else is wrong; tongue weight is too little, hitch is too low and the trailer is pivoting on the front axle rather than the rear, the axles are not parallel with the trailer loaded, or the axles are too far forward.

One other thought, it is mentioned the sway happens in higher winds. Sway can be result of soft sidewalls in tow vehicle tires. I tow a 35 foot trailer and my buddies tow 29s and we will run 80 pounds air in tow vehicle tires. Never any sway, even in near blow over side winds.
 

Reg2view

Well-known member
Feb 1, 2010
1,921
1,039
113
Your are dead nuts right on the E's and tire pressure; peeps will argue that it's overkill and that their C's on a 1/2 ton shorty are not under-tired or under-trucked in bad conditions. Not a coincidence that these are the rigs you see along the road and not on it when conditions go bad. A pro trucker can keep any rig on the road; only a small minority are pros, and pros are almost never under-tired.
 

IDspud

Well-known member
Nov 26, 2007
834
478
63
Oakley, ID
The pro truckers in our area park when the wind warnings start flashing but keep fooling yourselves.
When the wind lifts the trailer off the ground and sets it down four feet to the side tire air pressure is meaningless.

Don’t get me wrong, I pay careful attention to all that was mentioned and more, but to think you’ll conquer Mother Nature with skill, practice, prep means you’ve never ran in a real windstorm.