Top-5 towing myths

Don’t believe everything you hear about towing a caravan

If you think fake news is restricted to politics, wait until you hear some of the myths going around about towing.

Trawl caravanning forums or join a group at happy hour at a caravan park and you’ll get some great tips on towing, as well as hear some towing myths that seem to have a life all of their own.

Here are five of the most 'popular' towing myths….

Tow ball mass should be 10-15 per cent of the van’s ATM

This myth grew out of a rule of thumb in the 1970s, when a caravan usually weighed about 1200kg and 10 per cent (120kg) was about right for a relatively lightweight (typically a car) vehicle towing it.

Today a caravan often weighs 2000kg to 3000kg and the TBM of new vans now can be as low as seven per cent at Tare. Many such vans are perfectly stable when towing at Tare, and with a payload properly balanced may rise to only eight or nine percent.

Then there are the British and European vans, which typically have a much lower 4-5 per cent TBM. Sure, they also have a friction coupling to help avoid sway, but more importantly they have good inherent balance.

Basically, there’s no longer a hard and fast TBM percentage rule with new heavy vans.

Diesel tow tugs are always better than petrol

One of the main reasons for choosing a diesel tow vehicle over petrol is because the diesel is usually more efficient than the petrol, meaning that you’re paying less for fuel and you get a better touring range.

However, there are two reasons why diesel tow vehicles are not always the best choice. Firstly, if you have to pay a significant premium to buy a diesel vehicle over a petrol alternative, you might end up saving money with the petrol tow vehicle.

One example of this is the

petrol-only Y62 Nissan Patrol versus the turbo-diesel Toyota LandCruiser 200 Series. The Patrol Ti is currently about $16,000 cheaper than the GXL-grade LandCruiser – and that $16grand will buy you a lot of petrol!

Even within the LandCruiser range, if you pick the 4.6-litre V8 petrol GXL over the 4.5-litre turbo-diesel, you save about $5000. The LandCruiser TD isn’t all that fuel-efficient with towing anyway; you’ll average around 20.0L/100km with a big van behind, compared to about 25L/100km with one of the V8 petrols.

The other problem facing modern common-rail diesels is their technology - gone are the days where diesel was more robust and simple than a petrol engine. Even the most advanced petrol engine these days is more robust than a modern diesel.

Sure, specific engines do have known problems such as the KV6 blowing head gaskets in Land Rover Freelander or Jeep’s problematic 4.7-litre V8 from the late 1990- early 2000s.

The modern diesel’s injectors and fuel pump don’t cope well with contaminated fuel and can cost you tens of thousands of dollars in repairs to fix. Fitting an additional fuel filter and/or water trap does help to avoid this, although most diesel owners don’t think of it until it’s too late.

You need to use a load leveller

Some caravanners won’t tow unless a weight distribution hitch (WDH), or load-leveller, is fitted, in the mistaken belief that their rig would be dangerous without one. That’s

not always the case.

You need to measure how much the front of the tow vehicle rises when the caravan is hitched up. If the rise is more than 25mm, then before you even consider a WDH you need to check if your payload is balanced in the vehicle and van. For example, the heavy items should be loaded over the axles of the van.

If rebalancing payload doesn’t do the trick, then you might consider using a WDH. Even if you feel you have to use a WDH, be aware that it can cause big problems because of the enormous loads it transfers through the vehicle’s towbar and frame.

Even the most fervent WDH proponents go quiet when you mention this fact: you must release the tension from the spring bars when you’re going over a significant angle such as some driveways or spoon drains.

WDH manufacturers note this in their operating instructions, although what isn’t clear is exactly what angle is too much for a tensioned WDH.

Bigger the engine, the more fuel used

While it’s true that a smaller-displacement engine will typically use less fuel than a larger one, that’s not always the case when towing. With the extra mass of a big caravan behind, smaller engines can struggle, needing to get into the power band more often to maintain speed on the plains and have to work a lot harder when climbing hills.

A relatively

unstressed larger displacement engine can lope along, surfing on its torque curve and have far less need to dig deep into its power band in the higher rev range – and so use less fuel.

If the van sways, just lift off the accelerator

It’s a pretty sickening feeling when your

van starts to sway when heading down the highway, but just lifting off the accelerator isn’t always the answer.

If the sway is only gentle, sure, you just need to ease off the accelerator until the van begins to track true again. If, however, you’re getting a nasty sway developing, that might not be enough. Instead, you should hit the override button or switch on the electric brake controller to activate the van’s electric brakes.

You should also keep some pressure on the accelerator. With the van trying to slow down while keeping some pressure on the accelerator, you should still wash off pace (assuming that the trailer brakes are adjusted properly) but the rig will ’stretch out’, which should quickly stop the sway.

Vans fitted with override brakes are a lot harder to control sway, as there’s no independent control for the trailer brakes. The best way to stop sway in this scenario is to gradually slow down by easing off the accelerator.

Top-5 towing myths

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