A tow bar extension is an aftermarket accessory that you can purchase if you need your tow ball to stick further away from your vehicle. There’s a number of different types, but you should be careful with weights, and only run one if you absolutely need to.
What is a tow bar extension?
A tow bar extension is literally what the name suggests; its a piece of steel that makes your tow hitch stick out further, which can be necessary, or useful in some applications. For example, if you had a boat trailer that had the boat awfully close to your vehicle when turning, you could fit a tow bar extension which would shift the whole lot back, and give you the clearance needed.
I’ve seen people run them because they couldn’t open their door on the rear of a wagon, or a myriad of other reasons.
Be very cautious of them
Every time I see a tow bar extension though, it always sends shivers down my spine, because I know how much difference a bit of extension can make. This really only applies if you are towing something with a heavy tow ball weight, so if you have a garden trailer or something light its not really a problem. The reason they are a problem is due to leverage; when you increase the distance from the rear axle to the tow point you apply a lot of extra stress, and if you are off road this is amplified considerably.
As Archimedes said ‘if you give me a lever and a place to stand I’ll move the world’, leverage can do amazing things, and its not always in your favour. The further you stick your tow hitch out, the more leverage is applied.
Leverage is generally a bad thing, as it shifts the weight of the vehicle from the front to the rear, and you can end up with a huge amount of weight on your rear axles, and not much on the front. For example, a 300kg tow ball weight on a normal dual cab Ute without an extension will actually apply around 450kg to the rear axle. It does this by taking around 150kg off the front wheels and moving it to the rear, because of the leverage by applying weight so far behind the rear wheels.
If you fit a tow bar extension, you’ll find that the leverage is made even worse, and that can make an already sketchy setup really, really bad.
Beyond this, you need to carefully consider the stress it can apply to the vehicles chassis and tow bar. I’ve seen the chassis or tow bars crack badly when towing trailers that really aren’t that heavy off road, as the leverage once again applies significant force up and down, and eventually fatigue takes place, and you end up with steel or welds starting to tear. Not at all what you want to happen, especially if its on the chassis and isn’t something easily fixed.
Should you get a tow bar extension?
There are specific times where a tow bar extension works, and won’t cause you any issues. However, if you have a heavy tow ball weight, or are heading off road they are not a good idea, and you should steer clear!