D4 towing - trailer wobble

[Ruby2]

Ok so here we go. I tow a 700kg horse who is very dear to my heart

I have mainly kept to "B" roads and had no issues...however! Aha here we are travelling on the freeway....tootling along and get to about 80kph and get the wobbles from the trailer I think....like a wheel out of alignment. Tootle a bit slower trying to find a sweet spot and find it...at 88kph.

I get home and say to my poor suffering husband...the car? or float? has a wheel out of balance can you check them for me? Yep no worries, I love him he's a race mechanic, so off he goes and checks them...all seem ok...if anything one of the wheels on the car was slightly out...

So next trip it's not any better........hmmmmmmm

With the self-leveling suspension its quite hard to get the float draw bar level with the factory tongue. Suspect that there isn't enough weight on tow bar so put up with it for a few weeks and then today I have had enough. The float is starting to get a shimmy when it's going along and wobbling and with 700kg of lovely Spanish Mare (Australian Champion no less) I am not prepared to keep this going.

We did an experiment. We have a 1,000 water tank we use to water remote trees...we filled that about half full or say 600kg....slightly lighter than The Queen (horse) and I pack dogs and husband in the car to recreate what I am dealing with. Sure enough we get the wobble.....husband is thinking....I am thinking and I reckon it's the tow bar weight is insufficient so the trailer is skipping on the back of the car....
(I will also say that today as I was coming home I saw a car towing another car on a trailer. Nothing wrong with that you say? No of course not until the trailer starts to sway and gets up enough of a shimmy to cause what we call a tank slapper! Whammo, driver looses control...I flash my lights madly at oncoming cars and ring 000 as from what I saw it looked mighty messy!) So my impetuous to do something about this wobble was prodded you see.

To remedy it we flipped the tongue upside down so the ball is higher now....with the self levelling suspension it's not perfect but it's better after a quick test drive.

If you have any suggestions about anything else we can do I would appreciate it. With the tongue low it's too low and with the tongue high it's slightly too high BUT at least there is weight on the ball now!

I sure as hell do not want the anti-sway stuff on the car coming on with a 700kg horse in the back as they really are unrestrained and can fall easily so if you get stuck behind a float going slowly.....they are doing so for the safety and comfort of their horse...not to ruin your day or make you late :-)

[Graeme]

For starters, single or dual axles on the float?

Edit: From another of your posts its obviously at least dual axle. Therefore try lowering the pressures a little in the tyres on the front axle.

[connock]

wheel bearings tight ?

[discotwinturbo]

I tow a triple axle 3.5 tonne horsefloat....no sway at all.

It seems to be a balance issue. Too much weight at the rear, then it will sway at speed.

I would be checking ball weight, tyre pressures and wheel bearings.

I would expect it to be a dual axle horsefloat....if a single then I would never tow it with a horse. Saw a single axle one being towed by a cruiser in Harvey last year at an event. She said it was a bitch to tow.

Hope you work it out.

Brett....

[Ruby2]

Thanks everyone.

Yes dual axle double horse float with horse riding on the drivers side of the float.

Yep I think we didn't have enough ball weight either. Just interested what position is your tongue Brett? To get more weight on the ball I have had to flip mine. On the Hilux I didn't have this issue at all......

I couldn't even consider towing a single axle single horse float...wouldn't be strong enough nor stable enough!

[Ruby2]

Oh yes and we have checked bearings, tyres, balance etc. Float is less than 12 months old with only 15 hours total towing on road time!

[justinc]

definately sounds like more ball weight required. can you try a trip with 3 or 4 20 litre water containers on the drawbar, add and remove to experiment? you really need at least 100kg on the bar when towing tandem trailers with short drawbars, as many horse floats have. they sacrifice manueverability for towing comfort imo.

jc

[Graeme]

Are the springs load sharing? If not then the nose must not be down.

[discotwinturbo]

Thanks everyone.

Yes dual axle double horse float with horse riding on the drivers side of the float.

Yep I think we didn't have enough ball weight either. Just interested what position is your tongue Brett? To get more weight on the ball I have had to flip mine. On the Hilux I didn't have this issue at all......

I couldn't even consider towing a single axle single horse float...wouldn't be strong enough nor stable enough!

I have a Mitch hitch and rapid hitch. It's at the bottom of the 6 inch drop on the rapid hitch. When I had the LR hitch, it was the usual setup and not inverted. Basically the Mitch hitch is about 6 inches higher. They new setup sits at the same height as original.

Original and now modified setup are perfectly flat......but mine is heavy at 340kgs on the tow ball.

Maybe strap your 4 legged friend on the A-Frame

Brett.....

[Ruby2]

Thanks Justinc we have more weight now and not able to safely tow with more weight on draw bar.....set up isn't too bad...will try and post a photo but tow car will be my Hilux.
Graeme I have torsion bar suspension on the float if that helps....would have gotten rocker roller but didn't :-(

I will get a better photo tomorrow. It really is a pretty picture.

Sounds corny but for 20 years I have dreamed of having a lovely Disco and a matching horse float. Very Barbie but now I have it I am so tickled pink! Just get rid of this shimmy and we will be perfect!