Will Bias Ply Trailer Tire Sidewalls Flex Less than Radial and Help With Snowmobile Trailer Sway

Question

Question:

I have a V nose snowmobile trailer an have a lot of sway, the trailer company advised sway bays, weight transfer bars,and even max air in my truck and trailer. My question to you is could this sway be cut down by going to a bias tire for the trailor instead of the radial an what other problems am I going to create by doing this? It sways loaded or empty, if I use a taller vehicle like our motorhome its fine OR do I need a bigger truck?

asked by: Tim H

0

Expert Reply:

Snowmobile trailers are notorious for having sway problems due to their short lengths and wide construction. this makes it hard to load the trailer with enough tongue weight to eliminate trailer sway, especially at higher speeds. The best prevention against trailer sway is proper trailer loading.

Going with a bias ply ST rated trailer tire may help a bit because the tire construction is inline with the tires direction of travel and the radial tires construction is across the direction of travel. The radial tire will, as you have alluded to, have a bit more flex in the sidewalls where a bias ply will provide a stiffer ride. This could help a small amount with your sway issues, and if you need tires now would be a smart move. If you are currently running a passenger tire on the trailer upgrading to a bias ply ST rated trailer tire will provide a much stiffer sidewall for load carrying ability and could help quite a bit. Be sure to select tires that are properly rated for your trailer axle capacities.

I would recommend trying a couple of things before changing tires to bias ply, if you do not need tires right now. First, add some additional weight to the tongue of the trailer. A heavy toolbox or similar weight could be added to see if trailer sway is reduced or eliminated on a test run. Be careful and get up to speed slowly so you can monitor how the trailer handles. If tongue weight helps you can do what I did on an ATV trailer several years ago and add a tongue mounted tool box, like part # DZ91717P, and keep tools or other heavy items in it to compensate for the trailers low tongue weight condition. Adding a box to the front of my trailer eliminated all sway and made towing at highway speeds much less stressful. You would most likely need to put the box inside the V-nose of your trailer.

Finally, if adding tongue weight does not eliminate the sway issue you could go with an anti-sway bar, like the Reese Friction Sway Control Kit, # 83660. This will allow you to adjust the tension at the trailer tongue and help keep the trailer from swaying. You will need to remember to remove the sway control bar when backing in tight situations or damage could occur to the sway control or the trailer frame.

You would also need a draw bar with a sway control ball mount added. For a 2 inch ball mount use the Reese Sway-Control Bracket # RP26003 and for a 1-1/4 inch ball mount the Reese Sway Control Bracket # RP26005 can be used.

If you are running ST rated trailer tires, then you should definitely keep the tires inflated to the max pressure listed on the tire side wall. Your truck tires should be inflated to the manufacturers recommended pressure for your particular truck and the weight you are carrying in it.

Adding weight distribution will also help to control sway but, unless you have an issue with rear end sag on the truck, you should not need to add weight distribution for a snowmobile trailer. If you determine that weight distribution is needed you should select a system based on the actual tongue weight of your trailer, fully loaded and ready to travel. I have linked an article detailing some weight distribution information that should be helpful.