Ok I'm new to towing big trailers. I just got a 2004 F350 6.0PSD/Auto SRW. This weekend I was hauling a flatbed trailer (about 2000# empty) with a 79 F250 mud truck (about 6000#) on it. Truck had lots of pulling power BTW, but I found the trailer kept wanting to start to sway back and forth if I went much over 45mph. The trailer is brand new. On the way to the mud run I felt bad watching other Superduty trucks fly by me hauling there trailers and rigs. But everybody that I saw going faster only had jeeps and lighter trucks on their trailers. I didn't know if I was doing something wrong of if I needed to somehow load my trailer differently? What is the best way to prevent this?

 

You were too heavy on the tail, the load center needs to be further forward. Usually when the trailer wiggles a lot like that, this is the reason.

 

Yeah that would be my guess, the tail is too heavy, not enough weight on the hitch. You should be looking for 10-15% of the total weight on the tongue.

I would load the truck with engine forward to put most of the weight forward. Also any other stuff like tool boxes, ice chests etc can be used to help move load around.

You can weigh your trailer and tongue weight at public scales(truck stops, city dumps etc)

Also would be worthwhile to check tire inflation, truck and trailer. Also check that the payload truck is tied down so it doesn't move around. If the payload moves around it could start an oscillation which could then cause the rest of the rig to sway.

You might look at some antisway bars. They can make a big difference.

Good Luck,

Jim Henderson

 

Thanks for the help - I too assumed I needed a little more weight on the tongue. On the ride home I put the truck a little further ahead on the trailer(and I also didn't have 600# of tires in the back of it). The trailer didn't sway at all, but I kept my speed low as I was nervous, but I suspect it would have been fine. I've read if the trailer starts swaying to accelerate to once again put the tow vehicle in control - is this correct?? I know when my trailer started swaying I didn't feel like speeding up!!

 

Is the trailer sitting level? Are you or have you considered using a weight distributing hitch?

When a trailer starts swaying the most common mistake people make it to try and steer out of it. You should NOT try to steer out of sway but keep the wheel straight to recover from sway.

 

I had one break loose at 60 mph - I was going down hill, and all of a sudden it started to sway like mad, to the point of skidding. Luckily , noone was around me. I just fought to keep control of the truck, and it finally straightened out. Had I had trailer brakes working, I could have simply engaged the brakes and no more sway. I also learned that I could not load that trailer with motor end back. The trailer I have I can, but prefer not to.

 

A trick that I like is to measure a spot on your rear bumper with the trailer ready to load. When loading your trailer keep checking the spot that you measured until it drops about 2". That way you know that you are front heavy and the truck is not overloaded.

If you are only hauling one vehicle make some stop blocks and bring it to the same place each time.

my 2

John

 

Never heard of accelerating to stop sway.

Like the other guy said, don't try to steer out of it by correcting for the sway on each cycle, you will just make it worse. Most manuals recommend just hanging on and slowing down gradually.

If you had a brake controller, you could tap the activate or emergency button which applies only the trailer brakes and that should straighten things out. I would experiment with this just to get a feel for it. We never get to practice this until we are in trouble.

Good Luck.

Jim Henderson

 

Yah that is exactly what I did. I didn't try to steer out of it because I knew that would make it worse....I just held on tight and slowed down. I wasn't sure about using the manual lever on my brake controller, but it makes sense it would work. Thanks for the help.

 

I've never heard of this either.

Yep, same thing I do although I've hardly ever had to do it. Definately a good idea to practice so that you are prepared when it happens.

 

I would think accelerating would make it worse. On my experience, I just kept stabbing the brake and holding on trying to keep the truck under control, wasn't to worried about the trailer at that time, just wanted to keep the truck straight, not out of control.

 

While I've never heard of speeding up to stop swaying, what I've done on occasion is when I see a large truck coming up to pass, I slow down a little to "wait" for him and then slowly accelerate as he passes. This certainly helps to prevent a lot of the sway.