I tow around 9500 with a 16 screw 5.0 3.55 rear like its nothing and get 13mpg loaded while doing it. Eco "should do it a little better" except for mpg

 

Agree, the truck can handle the weight. There is something else going on. The only time I had sway problems on my 2012 was towing the enclosed car hauler empty in strong cross winds.

 

Again, towing the same trailer, same hitch setup, etc. with my 13 Screw was absolutely fine. Going to a 15 would provide stiffer frame (according to dealer I was at on Monday) and less weight, but no other significant reason for towing issues. I fully agree with running across scales, and plan to do so, I have that at the manufacturing plant I manage, but the only question i have there is this: I followed the instructions from Reese on setting up weight distribution, measuring unloaded distances to wheel wells, adjusting ball height and tilt, etc. Truck and trailer sit perfect when connected. Was at the local "expert" camping dealer yesterday, and he inspected same measurments and adjustments, and said everything is set perfect. Granted, its not a scale. But if I were so far off on weight distribution to create such a dramatic issue, would I not see something not setting right in the setup? If the only way to tell your WD is set correct is to scale it, would Reese not tell you to do so? And, like I said before, hauled this trailer many, many miles with my 13 with no issue.

If it were tires, taking the majority of the weight off of them, as I did in final test yesterday, would prevent any squatting and avoid the swaying, which is what I noticed.

 

That doesn't make any sense to me. What induces the side-to-side sway? If the tires aren't supporting the weight, then what is?

 

My thought, feel free to challenge.

If there were no WD (which there is, just bear with me)
Tongue weight would be significant. The rear of truck would squat significantly, and there would be significant weight on rear tires. The front tires would then have very little weight due to the lever effect with the rear tires being the fulcrum.

With WD, you adjust the springs on the setup so that the truck has about the same amount of downforce on the back and front tires at it would unloaded. Obviously you have some extra weight, but you are distributing the tongue weight across the four tires of the truck and the four tires of trailer.

So, to make math easy, lets say there is 2000# on rear tires and 3000# on front when unloaded. When attaching the trailer with WD, you are adding 1000# of tongue weight, but distributing equally over the four axles, so 250# extra on the rear.

If it were the truck only, wind would not easily move the rear of the truck enough side to side to have the sidewalls of the tires flex, allowing for lateral sway. However, if you think about a 30X8X8 7000# sail that is a camper, there is more surface area to pickup the crosswinds. This would increase the lateral force on the sidewall of the tire. If they are minimal ply, such as mine, they would flex. And at higher speeds, the problem would become worse.

By hooking more links on the WD, you are adding more spring to the trailer/truck connection, thus moving that 1000# of weight more to the trailer and front tires of the truck. With this logic, you know have taken the weight off the rear tires, and they are less likely to flex or be felt when they flex, so you lose the sway. You also lose all traction, as there is very little downforce on them.

Someone tell me i am wrong, I am willing to listen, but this is my hypothesis.

 

Sort of. But, from a guy who's spent more than a little time on a truck scale, you never come close to empty weight on the drive axle. The WD bars act to apply a torque on the frame of the truck to lever weight back on the front wheels, but the majority is still carried by the rear axle. I don't have the weight tickets anymore, but I remember scaling before and after the WD bars were tightened on a 15,000 lb trailer, and it was only capable of putting the front axle back at empty weight. The rear was still ~1,200 lbs over empty, and that was with the bars cranked as much as possibly. You just can't move that much weight with conventional WD tech.


Right principal, but it's nowhere close to equal. If you have 1,000 lbs of tongue weight, the rear axle is still shouldering at least 6-700 lbs in my experience. That's why I'm so interested to see your weights on a scale.

All tires will flex. Just for the record, just about all radial tires have only one ply, and they've been that way for years. You'll notice they are listed as a "ply equivalent".

Tire Tech Information - Load Range / Ply Rating Identification

Anyway, the majority of trailer sway is typically caused by insufficient tongue weight. This means that, under certain conditions such as hills and bumps, the tongue can actually be pulling up on the hitch, which places the trailer COG behind the trailer axles. This causes a cantilevering effect on the tow vehicle, as any lateral motion will attempt to magnify itself.

WD hitches act to control sway by placing weight back on the steer axle, and this gives them more traction to resist sway with. Your new truck is at least a few hundred pounds lighter than your old one, so it's also possible that you need a bit more strength from the WD bars to put things back in balance.

 

Basics:

 

OK, at a complete loss and feeling defeated.

The plant I manage has truck scales, so I took the advice and checked weight distribution:

Truck and trailer, combined: 11980
Truck only: 5880
Trailer only: 6100
Front tires of truck only: 2980

Seems pretty well evenly distributed, and looks level when sitting. I followed the Reese instructions posted above when setting up.

Bought new tires. Four new Discoverer AT/3, load rated E, 10 ply sidewalls. Improved, but still does not feel right.

This morning, hooked my camper to my buddy's Chevy with my hitch, WD, sway control, etc. Given, he has a 2500 Chevy diesel, so its not apples to apples, but surprisingly my hitch and spring settings worked perfectly on his truck. Down the highway at 85 MPH, could barely feel camper behind you, nor did you see it move.

Hooked back to my truck and had him drive. Even at 55, feel it swaying behind truck way more than either of us feel you should.

Verdict: No clue. I am leaving for our trip in the morning, probably will not drive over 55 the whole way to DC. Hoping to find a Ford dealer to get the truck into along the way. Only good news is I have isolated it to the truck, nothing wrong with the camper. Springs, frame issue, rear end issue, aerodynamics, I have no clue, just very, very frustrated.

 

Sadly, you didn't measure the critical values - the weights of each axle with and without the trailer. The biggest question is what's on the truck's rear axle unloaded, and with the trailer attached. Most likely, you either have too much or too little tongue weight, which will cause this problem. Looks can be deceiving.

 

need to go to a catscale and get all the axle weights. If you are passing thru Hagerstown, md then there are several at truck stops there.

 

Sent the OP a PM asking him to give me a call.

 

I'm going to hazard a guess that there's too much weight on the rear.

Now I have no clue what the weight distribution is on an unloaded Screw F-150 is, but I'm going to hazard a guess that it's in the neighborhood of 65:35, with the majority of the weight on the front axle. Assuming that the empty weight is in the neighborhood of 4900 lbs (this is a SWAG, so I'm kind of winging it), that means that unloaded, there would be in the neighborhood of 3185 lbs on the front axle. The OP says that the rigged weight is 2980? That implies to me that the front axle is unloaded maybe as much as a couple hundred pounds?

Just noodling here a little bit, but that's where I'm going.

 

JRW, get the axle weights both WITH and WITHOUT the WD system engaged. It's a little bit of pissing around at the truckstop, but it's less hassle than buying new parts for a truck when you aren't sure you need them.

 

Did your dealer install a Reese Straightline hitch? If so you might want to double check that your cam arms are adjusted right. After you get your bars set to the link that you want them pull straight ahead for about 100 ft without turning the steering wheel AT ALL. The top of the curvature for the bars should be sitting dead level and even on both cam arms. You will have to lay down on the pavement and look close to tell if they are even. When I put mine on I had it slightly out if adjustment and the sway bars were "fighting" each other and the sway controll was much worse than my old friction bar set up. After I got it dialed in right it works much better than any away controll that I have ever used. I will also add that stiffer tires will help. I went from the factory Goodyear wranglers inflated to 44 psi to Load range E BFG ATRs at 75 psi and it made as much difference as the hitch dialed in correctly.

 

Guess jrw1754 never made it back from the trip? Hello jrw?!?