Tips To Prevent Sway When A Semi Truck Passes You

Question:

i have a fastway weight distribution hitch with two weigh sway which I didnt buy from you. I was going to south on I-5 south of Albany Oregon when a semi passed me causing my trailer to sway. I ended up applying the trailer brakes to straighten it out. My question is why it swayed when the hitch supposedly has sway control on it. Is it possible it is not set up right? Ive never had issues like this before with any trailer Ive towed in the past. the trailer we have now is a coachmen Apex 21 ft and my tow vehicle is a 2017 Chevy Colorado with the 4 cylinder diesel w/6 spd auto and it has the z71 suspension. The only time had any severe swaying was from semis passing by. Any suggestions for future towing I could do.

asked by: Robert Z

Expert Reply:

I am happy to help with your sway issues. To fight trailer sway your best defense is proper trailer loading. If you can load your trailer so that 10 to 15 percent of the total weight of the trailer is tongue weight you will be doing well. The purpose of weight distribution is to take some of the tongue weight and actually distribute it back up to the front axle of the trailer which will also help with sway. It will also help with sagging rear suspension and improve handling/braking. Sway control does help with some sway from intense wind or from a passing semi-truck.

Another thing that can help stop sway that starts from a semi truck, is to use the manual override lever of your brake control to smoothly apply the brakes of the trailer. That will quickly stop the sway.

It could be that your Fastway system isn't rated high enough for your trailer. The best way to pick out a weight distribution system is to base it off of the loaded tongue weight of the setup when it is loaded and ready to tow. This figure also includes the weight of any cargo behind the rear axle of the tow vehicle. I attached a help article on determining tongue weight for you to check out as well. You will want the loaded tongue weight of your setup to fall right in the middle of the tongue weight range of the system you use.

There are weight distribution systems that come with sway control and there are basically 2 types of sway control; one prevents sway from starting and one reduces sway that has already started. I prefer a system that prevents sway from starting because if it doesn't start it won't ever be a problem!

There are a few systems that can prevent sway. First my top recommendation is a Reese Strait-Line systems such as # RP66084. It uses dual cam sway control to keep the trailer straight while towing so it won't sway. This system is rated for 600 to 1,200 pounds tongue weight. For a 2-5/16 inch ball use # 19286.

Blue Ox has the SwayPro systems such as # BXW1000 rated for up to 1,000 pounds tongue weight. This system limits travel of the spring bars at the chains and at the head to prevent sway. The 19286 ball will also fit this system.

And we have a friction type in the form of the Equal-I-zer hitches, # EQ37120ET, rated for up to 1,200 pounds tongue weight. It limits movement of the spring bars at the ends and at the head but does not use chains. It comes with a ball.

If your tongue weight falls outside of the ranges of the systems above let me know and I can make other recommendations. I have linked a video review of how these systems work as well.