Do you need a tough tow truck?

A big work truck can make sense for towing a heavy caravan

Head to your local caravan and camping show or expo and the array of vans both big and small is dazzling, if not confusing.

While there‘s any amount of information available on the specs of any given prospective purchase, there’s usually scant information when it comes to tow vehicle requirements.

The sad fact of the matter is the sale of the caravan is paramount in the minds of some retailers and your ability to tow it safely and legally is often not part of the transaction.

There are some like Bushtracker that try and do the right thing, and will even go so far as refusing a sale if it’s not a good match for the buyer’s tow vehicle. The company reckons a potential buyer at a recent Melbourne show was knocked back after it was discovered he wanted to tow one of their large off-road vans with a Jeep Cherokee.

“Sorry sir, we will not sell you this van for towing behind that vehicle. You will need a Ford F250, Silverado or Dodge Ram or similar type vehicle to be compliant with the law,” was the salesman’s response.

Apparently, the show-goer was a little miffed they wouldn’t take his money and stormed off, only to return later to offer a smug comment to the honest salesman that “(no names-no pack drill) just sold me one of their vans of the same size, no problems or questions asked so there!”

Well that was the start of another potentially bad situation on our roads and unfortunately it probably happens in every state and territory around the country with great regularity.

You’d think there would be many tow vehicles capable of towing caravans around the 3000kg mark but perhaps not. Inevitably, there needs to be modifications to suspension, tow bars and occasionally chassis or, as I did, choose something a bit different to the norm…

WHEN A ‘CRUISER WON'T CUT IT

Let’s look at my 2008 Regal 22ft 6in semi-off-road van that I call home and have done for almost two years. Being my only abode I tend to shop big when in a large town with an eye on savings, quality and availability of food stuffs, and the 215 litre Vitrifrigio fridge freezer has its work cut out.

To make remote living more comfortable and practicable, I also have a Waeco 110 litre fridge running at -15C for bulk frozen goods as well as a Waeco 60 litre fridge for drinks and food on the back of the tow vehicle.

The van’s plate rates the Tare mass at 2575kg with an ATM of 3070kg.

However the GTM (the maximum weight of the trailer when its axles are placed on a weigh bridge while it’s attached to the tow vehicle) is off the scales. It’s 2750kg, with the reduction in weight reflecting the high tow ball mass of 320kg.

Crunching the numbers, I have a payload in the van when detached of 495kg but just 175kg when hooked up to the tow vehicle. So the van, bare empty but with 300 litres of water, is now overloaded by 125kg!

Loaded up and heading west, I have every nook and cranny in the van crammed with supplies. These include two full 9kg gas bottles at 36kg, three 125Ah batteries at 45kg apiece, three full 90 litre water tanks, two jerry cans holding 40 litres on the front, and 100kg of food and drinks (not counting those in the tow vehicle).

Throw in a 15kg BBQ, 100kg of awning and annexe, water and sullage hoses at 40kg, 50kg of clothing to cover a few months at all temperatures and personal effects at 25kg.

Do the maths and that’s at least 800kg-plus payload pushing the ATM to around 3400kg, which is more than 600kg over the allowable GVM of 2750kg.

How did I get rid of the excess without going to Jenny Craig? Well, I transferred excess weight to my heavy-duty tow vehicle, an Isuzu NPR-300 medium truck, but that brought about another problem. With all my tools, fridges, metal detectors, spare truck wheels, two 105Ah batteries for the fridge and freezer and solar panels to keep them fed, I exceeded both the GVM and GCM on the truck.

I carry my pest management equipment and a two-man 4WD buggy and ramps on the back as well which didn’t help things.

The problem was also exacerbated by the truck’s high, 3800kg tare weight, due to the super heavy-duty steel tray and head board fitted. Being an ex-gas mining company 4WD truck it was built like a tank to survive the rigours of the outback.

The towbar is engineered and rated at 3500kg and both tray and tow bar have engineering certification and a plate nailed to the body to prove it. I then put the truck with full tanks (2 x 140L diesel, 1 x 140L petrol for the buggy and 1 x 86L water back up) on the weighbridge and the GVM showed 5987kg. That was a shade under the rated 6000kg so I had an engineer inspect and issue a new specification plate for 6500kg.

However, it didn’t take long to fill the truck with more gear, and now I have a GCM (combined weight of truck and van) of 9500kg and I am knocking on that door…

LONG LIST OF MODS

Having a heavy rigid truck (over 4500kg GVM) requires an appropriate licence, which in Queensland is ‘HR’. Then there’s the long list of modifications required to turn it into a semi-comfortable, all-terrain cruiser.

Being a big-capacity work truck, the suspension was hard and unforgiving. The steering was also a cot case, with enough over- and understeer to make it dangerous riding over bumps like expansion gaps on narrow bridges with oncoming traffic.

To prevent an old back injury from flaring I fitted a Stratos low-profile driver’s seat. I also installed a new set of custom-made Dynamic Springs which along with improving the ride and steering also provided a handy 50mm lift in the front and 130mm lift in the rear when detached from the caravan. It all sits level with 320kg sitting on the tow ball.

Another important addition was an air ride tow hitch. The tow point is so far behind the centreline of the rear axle that excessive strain is put on the drawbar and chassis travelling over undulating surfaces. The other benefit of the air ride tow hitch is that it allows us to carry glasses and crockery in the van without fear of smashing them on rough roads.

In most cases, modern vehicles straight off the production line are not designed for heavy-duty work so be prepared to invest in aftermarket modifications for both safety and comfort if you too decide to go down the tow truck route...

Do you need a tough tow truck?

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