DRIVING/TOWING - TOWING
During our Camper Trailer Torture Tests we encountered some problems with trailer electrical connections, but we also witnessed the results of the strange trailer towing choices that some 4WD enthusiasts make.
Nearly everyone tows something these days, in contrast to the majority of solo vehicles that used to be the norm in the Outback only a few years ago.
There are still some questionable zones for trailer towing, such as the French/QAA Lines across the Simpson Desert and a full-length Canning Stock Route, but just about everywhere else seems to be towing territory.
We wouldn’t choose to tow a trailer on the more demanding tracks at Cape York, but plenty of people are doing just that.
It’s the plethora of towing vehicles out there that gives us concerns about the safety of our relatively laissez faire towing laws. When all we could pull was a plywood van or a box trailer full of canvas tent and Eskys behind a naturally aspirated, 60kW diesel 4WD there wasn’t much threat, but today’s car-licensed driver can haul a three-axle, 4.5-tonne caravan behind a 350kW 4WD at 130km/h in the NT.
A high wind resistance fifth wheeler caravan can bob behind a ute driven by a car-licensed driver and overtake a prime mover and semi-trailer whose pilot requires a combination vehicle licence that takes years to acquire.
It’s not just the average 4WD driver’s lack of knowledge about the behaviour of long, heavy vehicles that worries us: it’s the ad hoc braking balance issue.
Buy a heavy caravan or fifth wheeler and it comes with electric brakes that can be regulated by the driver on the run. A truck and semi-trailer combination has braking that’s governed by an Australian Design Rule that prohibits any driver adjustment or modification.
Many caravan towers like to have their trailer brakes come on in the first few millimetres of brake pedal travel, to keep the combination stretched out while stopping.
It sounds good, but if the adjustment is too aggressive the trailer brakes have the job of pulling up the whole combination and those little stoppers aren’t designed to do that. Trailer brake fade or failure is an ever-present risk.
We recently followed a 4WD and caravan down a steep, winding hill and were horrified to see the trailer wheels locking and smoking the tyres at every bend. Yes,
we stayed behind him!
Much of the towing trouble we’ve witnessed is weight-related. On our 2010 Camper Trailer Torture Test we came across a bloke towing a monstrous caravan on the Borroloola-Roper Bar Road.
He filled our ears with complaints about the unreliability of the tyres and suspension on his 200 Series.
We had a close look at the combination and asked, innocently, if he knew what the ball weight was, before he torqued the weight distribution bars to breaking point. He wasn’t really sure, but guessed it was somewhere between 250kg and 350kg.
The 200 Series is a tough machine, but it ain’t that tough – nor is any other 4WD wagon.
People who think they need to carry all the comforts of home with them might be better off staying there in the first place.
Issues that affect all of us when towing off-road trailers are coupling designs and the flimsy nature of common electrical connectors.
Couplings that are complicated and need lubrication are certain trouble in the Outback, because dust or mud converts the grease into a very effective grinding paste, or jams the metal moving parts so that they won’t lock or release.
I know that rubber block, pin-locked couplings can be a pain to connect when your 4WD and trailer are on uneven surfaces, but they’re boringly reliable.
The most popular electrical connections are bush unfriendly. Car-style seven-pin plugs aren’t dust or waterproof, or vibration resistant and neither are Anderson plugs.
It’s quite common to see 4WDs with loose electrical plugs and many a disappointed camper pulls up at the end of the day to find that the trailer fridge isn’t working, because the battery went flat after the charging lead shook loose, or shorted out during a river crossing.
If these are the connectors you’re stuck with, move them from under the towbar, where they get bashed or stone hammered in even mild rough road conditions.
Another trailer issue is wheel bearings, so it’s important to carry a wheel bearing replacement kit or two. These kits aren’t bulky and ensure you can do a roadside repair if you have to. This Supercheap Auto video shows how the job’s done: