Seeing a caravan swaying on the road makes me nervous, not only for the poor driver trying to control their car/caravan but for the other drivers around that caravan. It got me wondering what causes a caravan to sway, and how can we effectively stop it from happening?
I’ve done a little research and here’s what I found.
A caravan’s sway is caused by its tow hitch being located well behind the tow vehicle’s rear axle. When the tow vehicle yaws in one direction that overhung hitch causes (not just allows) the tow vehicle to sway in the other direction. Likewise, caravan sway causes tow vehicle sway.
Below are some ideas to help stop your caravan swaying:
Ensure your tow ball weight is not too light
When your caravan is hitched up, some of its weight s transferred onto your tow vehicle through the tow ball. This tow ball weight is known as tow ball download, and if it’s too light it can make your caravan sway.
As a rule of thumb, your caravan’s tow ball weight should be about 10% of its total weight (Aggregate Trailer Mass)
Check your compliance plate. This might tell you the tow ball weight.
Make sure most of your weight is over the axles, rather than the front and rear of your caravan
Some people start with a tow ball weight that is too heavy, this can be because of either:
• Trying to offset too much weight on the A Frame, or
• A caravan that isn’t suitable for the tow vehicle.
One of the worst things you can do to try to lighten your tow ball weight is to move weight to the rear of the van, this can lead to severe caravan swaying, and or snaking all over the road.
Tow with your caravan with your water tanks full
You don’t always need to tow with your tanks full but it does help, especially if you need to off-set your caravans high centre of gravity.
Full tanks can help stop your caravan from swaying for 2 reasons
- A bigger proportion of the weight is down low, so it lowers your caravan’s centre of gravity, and
- It increases the proportion of weight that is over your axles.
Select the correct tyre pressure based on how you are loaded
This all depends on your tyres, and as well the amount of weight you are carrying, also how it is loaded.
If your tyre pressures are too high, you’re in for a bouncy ride, and you will wear out the centre of your tyres very quickly. Not only this, but you’ll sway more and can lose traction on the road.
Reduce your speed! This is a sure way to stop your caravan from swaying
Speeding is a prime cause of caravan swaying,
If your caravan is swaying badly, relax and loosen your grip on the steering wheel. Hold your steering wheel firmly but relax as much as possible so you’re not locking your steering wheel into a fixed position. Reduce your speed. Lift your feet off the pedals and avoid braking as this will slow the tow car down too quickly for the caravan.
Consider fitting electronic stability control (ESC)
ESC is proven to be effective in reducing the occurrence of single vehicle and roll over crashes. It is a braking system that automatically controls the behaviour of your caravan. The electronic stability controller monitors dangerous lateral movements, taking action where necessary via the electric brake system, to maintain your road position and provide you with peace of mind.
I hope some of this information has helped with understanding swaying and its causes.