Caravan Tips - Why do caravans sway and how do you stop it? 

I have to admit that I was of the thinking that accelerating the car would sort it out. So this was most educational. Thanks.

I saw a demonstration with a model car and flat bed trailer simulating a caravan. The instructor showed by moving weights forward and then to the rear of the trailer, that if weight (like a full water or sewer tank ) is moved to the rear of the trailer , then that's what makes the caravan snake and sway. Emptying the water/sewer tank ( lessoning the weight) will completely remove the tendency for the caravan to snake. Easy fix.

I am surprised you’ve not mentioned what can start this sway. Most importantly loading your caravan correctly with the recommended tow hitch weight. Elements to look out for out on the road. Cross winds you mentioned. Coming to a downhill section where your hitch weight goes light. Driving out of a sheltered cutting into a cross wind. Etc,etc.

I am surprized that no one knows what to do if a caravan or large trailer starts to sway, A swaying caravan or trailer will start steering the car in either direction, Do not try to fight this as you will only make things worse, Lock your arms and steer straight ahead take your foot of the accelerator, do not apply the brakes or accelerate the vehicle, You can apply the trailer brakes if you are able. I have used this method and it does work. If the problem persists you will need to proceed at a slower speed & fit anti sway bars to your vehicle

Unfortunately all Aussie outdoor/4wd/getaway types of shows are just big ads for their sponsors.

As a beginner this is valuable info, thanks

Love that they used LEGO at 1:07 and 2:07.

My van ins 19 foot long in the body and manufactured before the ESC systems were available. I do have the electronic brake control unit within reach for manual application ( hit the bottom to apply the brakes), but I am not sure if I would have the presence of mind to get this done when the van was suddenly swaying. I have sway bars/ levelling hitch fitted, I load my van toe heavy, and limit weight to what we really need/ use, plus travel at 90 -95 kph. I can drive at 100 kph, but it feels more reactive to road conditions.

And one last point is that any water or fuel containers, where the fluid will slosh from one side to the other, should be above the axle or if not possible, forward of it.

3:45

We have a 6.3 metre European caravan with a BPW hitch (which I imagine is similar to AL-KO), and friction pads in the hitch cup (I'm sure that's not the proper name!). We regularly drive Brisbane to Sydney, and can tow at 100km/h. We've never had any issues with swaying (even with wind, passing semis etc.). We often see Australian made caravans start to sway from 80km/h upwards. Can there be that many other caravanners who don't set their caravan up for proper towing?

if differential axle is installed in caravan? could the sway effect be reduced?

Don't worry - they stop swaying once they tip over..

I'm about to buy a van and I'm a bit overwhelmed by the responsibility to stay safe. Also have never worked out why caravan always have two axles. I'm not thinking axle weight here but extra brakes Cars have 4 wheel and a caravan can weigh just as much

If you suffer from caravan sway and survive, take the hint and SLOW DOWN! You are towing way too fast. PS if you pass a semi that is doing 100km/hr, you WILL get sway. Semi's push a massive amount of air around the front and the pressure differences as you go past will try to blow you off the road! Tow at sensible speeds!

and another bs***t that load balacer.... you only need a Winterhoff sway reducer and properly load the trailer. just take 5 more minutes to think things thru

Also a little trick for tandem axle trailers, run approximately 15 to 20lb more air in the rear axle than the front. Before all the experts weigh in their opinions try it. For the tech guys the longer the distance between the tow ball and the rear axle the greater the stability

Okay, the "experts" have come up with a few theories, now I will throw one into the ether... Most of the problems come down to the type of suspension that is fitted to the caravan. Most of the single axle caravans have a leaf spring suspension that is fixed at the front of the spring to the chassis, and the rear of the springs are 'slipper' type, as in they have a bracket that the end of the spring sits in and moves forward and backwards as loading / road conditions vary. Because the road conditons vary, this means that the springs are flexing; mostly not equally with each other. Because the front of the spring is fixed, and the centre of the spring is fixed to the axle, this flexing of the spring can alter the distance between the two points. By having two different distance between these two fixed points, this changes the angle of the axle, and now you have the axle of the caravan steering the caravan! This was often seen with a 3 axle dog trailer, single axle dolly on air suspension, with a tandem, short wheelbase trailer behind that. The best way to counter this problem is to select a caravan with a torsion bar, slipper spring suspension. This works by having a fixed bar that is connected to two fixed points; one being the axle, the other being the chassis of the caaravan. By doing this, you are now removing the geometry of the self steering axle from the equation. By having the springs on slippered ends, and having a solid fixed radius that the axle can travel through, you should be eliminating the sway from your journey.

Q; Why do caravans sway? A; Because they are pig trailers. They also pitch for the same reason. Q; How do you stop it? A; By making them as dog trailers.

Caravan advice from a bearded hippy, playing with Lego. Reckon he'd been easier saying; If your caravan starts to sway, stop it with fire, and buy a bloody van!😏 If you learned anything from this video, then you probably shouldn't have been towing to begin with.

it is beyond my undestanding why this trailes do not have inertial mecanical braking mandatory in EU. just slow down (no braking), as they teach in driving school, and the trailer will brake on his own and recover. very very strange

What a dumb article. Set up prior to starting out is critical. Tongue weight, correct tyres an d pressures are a start. Braking when the trailer is on full sway will cause an accident!! Light braking as the trailer is coming back into line is the only way. However the correct setup and moderate speed is imperative.

I don’t think this helps with a heavy trailer with no breaks and a vehicle with too small breaks to stop it. It’s my experience to take your time and when it happens let off the accelerator and ride it out. It’s nice to give faith in equipment but it’s not always there.

This video does is not very useful. It even gives bad advice. Applying brakes to a swaying caravan will increase the magnitude of the oscillation. The only saving grace of this advice is that by slowing the combo, the overall forces will eventually diminish. Increasing speed is not the answer either, because although it will have an initial alleviating effect, the extra speed will compound the difficulties of stopping safely. The best solution is to ease off on the throttle and try to keep the rig on the road till it gets back to a safe, non-oscillating speed.. In fact, what this video doesn't discuss is that potential oscillating situations are directly proportional to speed. There is a more or less fail-safe speed that any rig can do and this is mostly a function of the tow-ball weight to caravan GVM ratio (with input from stabilizing devices being an additional factor). Normally, this ratio needs to be at least 10%, but if one wishes to drive at highway speeds, one perhaps needs to carefully experiment first. I tow with a Ford Fairmont at maximum GVM for that car (1500 kgs). But to keep weight on my front wheels and not depress the back of the car too much, I actually tow at a tow-ball weight to GVM ratio of 5%. To do this, I restrict my speed to 80 kph. I determined this max speed after careful (and at time a little hair-raising) experimentation However, I do not recommend anyone else try towing at a ratio of less than 10%. The risks are just too great. Once that trailer takes over, it is very hard to regain control. What needs to be remembered also is that the axle to tow-ball distance is just one factor determining the tow-ball to GVM ratio. The way the caravan is loaded is just as important. A necessary piece of equipment for any caravaner is a weighing scale and small post to every now and then check tow-ball weight. Likewise, they should have an accurate idea of the weight of their loaded caravan. Finally, one needs to be on the lookout for oscillation. Towing a big rig is a serious business and small deviations need to be picked up immediately and speed reduced.

I just watched a commercial...

That is simply not quite correct - when the caravan starts to sway it does accelerate true but what happens next is Simple Harmonic Motion stops at 10 degrees of sway and is anything but SMH since the tyres grip the road against the sway and that forces the van to push the overrun brake on hard and then that releases the potential energy that accelerates the return towards the opposite side and this multiplies the next sway exponentially if the market leaders did their maths correctly they would know how to stop the sway from starting as I have done with "Differential Stability" all they have to do is contact me and I will show them how it is done without any electronics or motors. If the AlKO man stopped to think that if the caravan did accelerate it would apply the overrun brake - just put a camera on the hitch and watch - it is just like the water skier as he accelerates back and forth. ALKo system applies all the van brakes and that simply slows the combination down but if that occurs just as you are passing a large truck it can hold the combination in the slip stream of the truck at a critical point and remember it only takes 3 swings to become catastrophic and the ALCO system needs 2 full swings or 4 minor swings to actuate. With Differential Stability it is active all the time and will provide an equal and opposite force at or near the centre of equilibrium before the driver even knows it is happening. There are limits with anything even my system but my calculus calculations show it is way above normal road conditions - wind or inertia loadings. If you wonder why appling the overrun when you turn does not cause a sway it is because there is no inertia in the caravan so it will perform as it should. All this is related to overrun brakes - electric brakes are slightly different and if you have a caravan electronic switch that you can apply if a snake occurs be very careful when you apply it if it is not a differential system.

Just an ALKO ad really. There are equal and much cheaper choices on the market, shop around. And lets face it, if you are hooking a caravan up for a trip....What Is The Hurry?? Take it easy and enjoy yourself. Most swaying is due to driving too fast for conditions. Yes trucks can cause it to but be aware of your surroundings and road conditions. Basically, most of what these wankers sprouted is BS. More driver training, plain common sense and thinking about how you load the van is needed. All the so called 'experts' do is confuse the issue and make the 'beginners' fork out $$$ for unwanted gadgets

Put your boot into the towing vehicle till it stops don't brake the tow vehicle under any circumstances

Or just get a fifth wheel.

yall are driving on the wrong side of the road that's why its swaying

Axel steer. Few caravans and trailers have electric brakes. Pointless video. Just adverting a product.

Too much talk. Little advice.