WIf you want to attach a caravan to a car, you quickly realize that the height of the ball head of the trailer hitch above the ground varies depending on the vehicle type. In particular, the large SUVs and off-road vehicles, which are popular as towing vehicles because of their stable construction, are equipped with more ground clearance in favor of the desired ability to drive off the beaten track. As a result, the ball head usually sits higher. The result is that in most cases a caravan is not quite horizontal when it is coupled – behind the SUV the nose points more or less steeply uphill, behind a flat passenger car it can sometimes even go down slightly. This not only looks horrible, but also has an unfavorable effect on the vertical load and thus the handling.
So it’s no wonder that some owners of off-road vehicles are looking for a remedy. Although there are special off-road caravans such as the expedition trailer developed by Volker Lapp, they are expensive and less comfortable than conventional caravans. For the ordinary trailers, the obvious idea is to simply equip them with larger wheels.
At the same time, this increases the ground clearance off the beaten track, but often cannot be implemented without extensive work on the body because the large wheels do not fit into the wheel housings, and above all it is not permitted. Because the size of the rims and tires is part of the approval, the trailer’s braking system is tailored to them. Raising the axle using spacers sometimes works, and is also offered by some specialists, but the TÜV can then demand a reduction in load, which further reduces the already poor payload of the caravan.
The company Wohne United from Friedrichsdorf im Taunus is taking a completely different approach, which, in addition to all kinds of off-road mobile homes, also has a higher version of the Eriba Touring Troll in its range. “The Troll is particularly suitable for the conversion because, unlike other caravans, it has a stable tubular frame,” says Willi Klose, who worked out the technology and is the company’s technician responsible for the Eriba Offroad. Of course, some effort is required to give it enhanced off-road capability: the entire unit consisting of axle and towing device is removed in the in-house workshop and replaced with a much more stable construction specially developed for this purpose. In addition, the diameter of the brake drum is larger, explains Klose. At the same time, the drawbar is also 20 centimeters longer, so the Troll ends up at exactly 5.99 meters. “As a result, it runs more smoothly,” says Klose, “other than that, the driver doesn’t notice any difference to the original.
The comparatively light Troll runs quietly anyway and, with its pop-up roof when folded down (you should only drive at walking speed when set up), offers low air resistance compared to other caravans, but the unladen weight of at least 940 kilograms, depending on the model, increases by around 100 kilograms. That’s easy to get over, because the permissible total weight is now 1800 kg thanks to the new towing device instead of only 1300 for the original.
The high payload is one benefit, the greater ground clearance is the other benefit. The axle is 10 centimeters, another 15 can be reached with the larger tires that are now possible. The off-road tires are fitted with 225/75 R 16 tires instead of the smaller 14-inch tires that come as standard. The rough studs aren’t strictly necessary for the trailer, but they look better behind the SUV. The reward for the effort: the Touring Troll now has 52 centimeters of ground clearance and a better approach angle. Everything is 25 centimeters higher, which means 52 centimeters for the clutch. However, the total height increases to 2.50 meters with the roof folded.
The ascent entails further changes, so the standard crank supports are replaced by more stable ones. New and used Eriba Touring Trolls from the 530 to 550 series have been converted for around five years. There are about two dozen of them every year, says Klose. The price for the conversion has now been increased to 7900 euros. The cause is the increased cost of the parts, they say, and it takes a week of work in the workshop.