Camper Trailers Tech Tips

off-road couplings

 

 

off-road couplings

The majority of members in the Australian CamperTrailers Group own an off-road vehicle together with a purpose built off-road camper trailer & prefer to venture off the beaten track into the more remote parts of Australia. For this reason they have an off-road tow coupling which suits the capabilities of both vehicle & camper. Let's look at what off-road hitches are on the market & what sort of job they do.

 

An on-road BALL COUPLING has limited movement & therefore is not generally suited to off-road use. Major trouble can develop with this type of coupling off-road if the tongue bottoms out into the hitches casting & breaks a piece out of the coupling, rendering it useless.  Ball couplings as shown right with hydraulic over-rider brakes have a 360 degree rotation.

   

The PINTLE HOOK has its origins in agriculture & then developed for military purposes in the 1940's. The pintle coupling is not as popular as it once was.  It does have limited movement from side to side & can be noisy at times over rough terrain.

 

An improvement on the Pintle Hook is Vehicle Components VC COUPLING which represents a major breakthrough in the performance of ring type couplings. The key to its ingenious design is separating the ball movement from the clamp. The coupling locks a conventional ring into place so there is no play in-between the towing vehicle and the trailer. The base of the coupling incorporates a sealed ball joint which provides the articulation between the two vehicles. The lack of play in the coupling eliminates noise and damage between the vehicle and trailer and does not snag when reversing around tight situations. As the movement is fully sealed the coupling can be used in arduous conditions needing no maintenance.

 

 The TREG poly block coupling came about when Gordon J Tregoning pioneered the unique shaped coupling designed to make towing easier. With safety a key factor, the couplings 3 tonne capacity is suitable for all vehicles on the roughest of Australian roads. The ADR approved design has been made in Australia for over 60 years. It has a pin that stops full up & down movement , but has 360 degree rotation.

 

 

 The ORAC coupling enables safe & reliable towing in all conditions by providing a fully flexible coupling between the trailer & vehicle.

It features a special anti vibration bush to prevent damage to your vehicle or trailer on badly corrugated roads & tracks with a tow capacity rated at 2500Kg. It has full 90 degrees of pivot above & below the horizontal with a 360 degrees of rotation.

             

The HITCHMASTER DO35 V3 coupling is the latest design from Cruise Master, formerly Vehicle Components. The coupling is manufactured with components made from forged steel, high quality polyurethane & laser cut stainless steel which reduces weight & is over 50% stronger than the outgoing model. Features include a new ‘Checklock’ cap system keeping the dirt out of locking mechanism & also gives a visual indication that the coupling is locked. The low profile gives better clearance for rear open vehicle doors with a 2-stage ADR compliant locking mechanism.
 

 The OZHITCH is a simple drop in off-road hitch with a self aligning tool in the shape of a cradle which lines up perfectly the two halves of the tow hitch for easy connection. The two locking mechanisms only require one hand to operate, leaving the other hand to operate the jockey wheel. It is bushed so there are no rattles & lockable for security. The hitch design allows for 85 degrees of movement up & 70 degrees in a downward direction with a 360 degrees rotation.

 

 AL-KO has released three new off road couplings onto the market which fit a towball. They feature a patented positive towball latching system that make connecting a breeze, requiring no pin or hole alignment. The couplings are ADR compliant meeting Australian Standards & designed & tested in Australia for Australian conditions. The three versions available are a 2 tonne and 3.5 tonne fixed intended for used with electric brakes & a 2 tonne overrider for mechanical or hydraulic braking systems. All feature 360 degree head rotation. 

 

The HITCH-EZY 3.5 Tonne coupling features a convenient & safety feature mechanism that holds the coupling in the unlocked/ready-to-engage position for hands free coupling & uncoupling. During the self-centering engagement process, automatic double locking occurs with the full descent of the sleeve over the tow-pillar. The coupling is manufactured using marine grade 316 stainless steel & zinc-nickel alloy plating of all metal components prior to painting. There is unlimited articulation in all three axes with O-rings to keep the coupling area dust free. The coupling is compatible with level-ride torsion bar systems & has a low profile allowing clearance for 4WD rear doors. A tow-pillar, security dummy-pillar, aluminium pillar cover & stainless steel handbrake is included. There is also a 5 tonne version.

 

The ARK XO coupling offers full off road articulation & fits a standard 50mm tow ball. The unique Quick-Hitch locking system makes hitching up and unhitch an easy process. There are two sizes, a 2 tonne coupling designed for mechanical overrider brake systems & a 3.5 tonne coupling for electric brake systems.

 

The Lovells HAULACE 3.5T is an Australian designed, tested and manufactured all terrain coupling with 360 degree articulation. The head of the coupling is made from super tough Duplex stainless steel and requires no maintenance. Also available is a 5.5 tonne version.

couplings now out of production

The Vehicle Components AT35 COUPLING has a secondary means of automatically locking the primary locking mechanism in place. It is rated at 3.5 tonnes capacity & incorporates variable rate polyurethane bushes which absorb shock, yet allow the structure to take the maximum loading condition. Articulation is 70 degrees minimum in all combinations of movement. The low profile design allows maximum clearance for rear opening doors. The Vehicle Components standard handbrake is designed to fit to the rear mounting bolts of the coupling. There was an override version of this coupling also.

 

Vehicle Components HITCHMASTER DO25 Drop On 2.5 tonne has a two diameter pin & boss arrangement making it easy to connect just like a ball coupling. The chamfered area between the two diameters allows the pin to slide through the hole in the coupling at whatever angle the hitch may be. The DO25 has a simple hooking up procedure, just pull the T bar up & rotate until the locking plate moves in under the pins head. Simply letting go will let the location pin on the locking plate drop into its hole & at the same time the spring lock fixes the locking plate also.

 

Vehicle Components HITCHMASTER DO35 Drop On 3.5 tonne, is a bigger version of the DO25. The DO35 is rated at 3.5 tonne & has  the same safety features as the DO25 with two separate locking mechanisms. The machined surfaces makes hitching up much easier in awkward locations than other off road couplings that need a pin to be inserted. There is a small poly block for shock absorption between the trailer & tow vehicle.

 

The HITCHMASTER DO35 V2 is the result of continuous improvement & rigorous testing by Vehicle Components. It is rated for a maximum load capacity of 3.5 tonnes and complies with the Australian Design Rules 62/01 and 62/02. The coupling has a polyurethane bush on the pin, a double locking mechanism and a sleek safety cap which doubles as a visual aid to ensure the locks are engaged. It is very simple & easy to connect even on uneven ground. Off road it has full 360 degree rotation & 70 degree articulation. It is suited to all camper trailers and caravans for off and on road usage.

 

The HYLAND uses a ball coupling with a difference. The hitch is manufactured to give the ball full articulation with a 360 degree rotation, making it far superior to the old ball hitch in off-road situations. The Hyland hitch must be used in conjunction with a 3.5 tonne ball which has a higher stem than the standard 2.5 tonne ball. This allows for proper fitment of the Hyland hitch over the ball allowing clearance without fowling the tow tongue. 

 

The McHitch UNIGLIDE coupling uses a universal joint to handle all movements well past 90 degrees horizontally & vertically with the twisting being handled in the rear body by shock absorbing urethane bushes. The universal joint is the same found in all 4wd Landcruisers while the joint is held in place by registers and opposite threaded plugs & end caps which removes any end play. The universal and rear body are both fully greaseable.

 

The TRIGG polyblock coupling is rated to 3 tonne towing capacity & features brass bushes & 19mm locking pin. It has 360 degrees rotation & 90 degrees grease nipples for easy servicing.

 

 

 

 

information by Rob

updated march 2023