Are load levellers a waste of time?

Aussie caravanners swear by them but there are better ways to ensure a balanced rig

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While the Weight Distribution Hitch (WDH) is nothing more than a band-aid solution, its adherents support their use with venom.

Criticise the WDH, and you’ll hear shouts of ‘You’ll kill yourself!’, ‘The rig will be bloody dangerous!’ and ‘I won’t want to share the road with you!’

And so on.

It wasn’t always this way. Back in the 1970s, Aussies loved a caravan. It was around then that the 10 to 15 per cent rule (that is, 10-15 percent of a van’s Aggregate Tare Mass should be on the towball, or the Tow Ball Mass) became cemented in the Aussie caravan-towing mindset.

However, you didn’t often see a van that weighed more than 1500kg Tare or have more than 150kg on the ball back then. There was no real need for any weight-levelling devices, and for those vehicles that did need a bit of help to stop dragging their tail, the ‘Shepherd’s Crook’ load levellers did the job. The 10-15 rule made sense.

Our caravans were much simpler — and lighter — back then: air conditioning, a washing machine, an ensuite and onboard 12v power were unheard of.

By the 1990s, after a decade of sluggish caravan sales (hit by the late-‘70s oil crisis followed by a general preference for motels) caravanning was again on the rise.

‘Vans, like the vehicles towing them, got bigger and heavier as buyers’ desires for more interior room and more mod cons fattened up their ATM.

More weight was plonked on the towball too. Grimly hanging onto the old 10-15 per cent rule, vans were built to make the tow tug take a 250kg to 350kg share of the weight.

With this kind of weight on the ball, there weren’t too many tow vehicles that did not have a nose up, bum down attitude. That made for some pretty nasty dynamics.

Then came the WDH. Caravanners now had trusty big, thick steel spring bars that could shift up to 550kg away from the rear axle of the tow vehicle to the front.

Their tow vehicles rode level and they felt like they could actually steer and brake once again.

Then things came unstuck — literally. Some tow vehicle’s towbars were cracking under the strain when used with a WDH. Caravan forums ran hot, blaming the vehicles and their towbars for not being up to scratch.

Part of the problem is, not many caravanners read the fine print when they stick on their shiny new WDHs. In the instructions of a well-known WDH manufacturer, it actually says that the spring bar tension must be released when negotiating spoon drains and the like.

You see that all the time. There are caravanners stopped everywhere where there’s a spoon drain carefully fettling their WDHs. Stuck behind a van stopped at a steep servo driveway? Yep, he’s releasing WDH spring bars.

A Toyota engineer once told me the story of engineering the locally built large sedan, the Toyota Avalon, for Aussie conditions. Part of the testing involved towing.

Using a WDH set up at the correct tension to transfer the weight to the front wheels, the poor Avalon bent like a banana. They were even able to take back wheels off. The car stayed beautifully level though.

Maybe the Avalon is no tough 200 Series, but obviously what you’re playing with back there at the coupling generates massive forces.

It’s not just the vehicles that cop a hard time from the WDH. I met a bloke once who forgot to move his feet away from under the spring bar when he was releasing it. You know what’s coming next. He broke his foot and was in a cast for months.

The fact is the industry has moved on from the 10 to 15 per cent rule. Take Australia’s most popular caravan brand, Jayco. It’s not unusual to see 2500kg Tare Jaycos with just 140kg on the ball. How do they tow? Beautifully.

The vans have been designed to be balanced. Add your 400kg payload -- properly, not all your heavy stuff plonked in the front boot -- and towball mass will rise, but not by much.

There’s been an arms race with vehicle manufacturers pumping up their vehicles’ towing capacity. You have to wonder how well a 2000kg vehicle is going to tow a 3500kg van. A heavy vehicle, with a long wheelbase and short rear axle-to-tow point distance will always be a more stable tow tug.

Add to good caravan balance and good vehicle choice the use of new safety technology — trailer sway control and caravan ESC — and there should be no need for a WDH.

Part of the problem is that some caravanners fret over the idea that there’s all this weight on the back axle of their tow tug and all it would take is for them to sneeze for their rig to spear off the road.

While a WDH might be the only solution for especially ball-heavy vans such as an off-road tandem with the works, the fact is that towing a big heavy box is never going to be the most stable, dynamic vehicle on the road.

Chucking on a pair of massive spring bars doesn’t fix the real problem and that problem is simply a lack of balance.

Are load levellers a waste of time?

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