Why do all my trailors do this?

It seems that no matter what trailor I seem to haul, once I get up to highway speed, the trailor starts to wag. Large or small, they all wag, back and forth. I see it on the road alot, some construction trailor loaded with some mid-sized piece of eqpt., wagging back and forth down the road. What is it? Is it the placement of the load, or the lenght of the trailor, or what? HELP?
Why do all my trailors do this?

Make sure your tire pressure is up to the trailer manufacturer's recommendation. If they are, and the tires are not up to their maximum, you might try adding air to the tires in 5 pound increments. Inadequate tongue weight may also cause sway. Not sure what recommendations are now but back in the day we wanted about 10% of the towed weight on the hitch. If this is not accurate someone please correct me.
Why do all my trailors do this?

Hey Austin
Somthing you didn't mention is what you are towing with. Is the trailer too heavy for the vehicle. One time we were trying to tow a Cadilac with a Buick. The Caddy out weighed the Buick so once we hit 40mph we were all over the road. I don't know what the ratio should be for this but it is something to check on.
Why do all my trailors do this?

Hi! Austin, When towing a trailer the weight should be tongue heavy (I think Krazeehorse is correct.)and your speed should be less that when not towing. Speed sometimes leads to the tail wagging the dog. Have fun and be safe.
Why do all my trailors do this?

Some very good answers. Have you tried a sway bar? Are you using a torsion hitch? Are you pulling with a tank full of fresh water? Do you have radial tires on the trailer and on the towing vehicle? Are all the tires on the trailer radials or biased ply? They have to match. Have you checked the springs? I had one break and the first thing I noticed was a sway. Are you towing the trailer level? Is the tongue hooked to the bumper of the tow vehicle or to a trailer hitch? There are a few things that cause sway but the biggest one is having to much weight in the back end and not enough in the front.

Hope this gives you some things to check out. I towed trailers for a long time.


'02 Southwind 37U/Workhorse
'01 GMC Sonoma w/Brake Buddy