Glossary towbars

Universal HGV Towbars

We manufacture special tow bars for trucks and estate cars. The height and width of these are adjustable making them universally applicable. As an option, you can choose either the open-end or ball towbar.

Tow load

This is the towable load that can be attached to the towing vehicle. The automobile manufacturers specify the tow load for each vehicle type. Our specifications refer solely to the tow bar. The maximum permissible tow load of your vehicle is specified in your vehicle papers or registration (in Germany: line 28).

Automatic system

With detachable systems, the ball is only to be attached when necessary so that it does not to detract from the automobile's appearance. Automatic systems are renowned for being easy to use. To attach the ball bar, it need only be inserted into the receiving lug and it locks in automatically. When the ball bar is not attached, it can be stored in the boot of your vehicle, for example. Another advantage of this system is that you can secure the ball bar using the integrated lock.

Year of manufacture

If no year of manufacture is specified, then the vehicle type is valid for use from the date of its appearance until the present or until it is discontinued.


In accordance with legislation, the tow load (Germany: GA) and maximum permissible total weight (Germany: GF) no longer need be specified on the type plate. Only the D-value and the permissible support load are specified. Using the specified D-value increases the possible bandwidth with modification approvals in accordance with paragraph 19 (3) StVZO in Germany. For example, by accordingly varying the tow load it is possible to change the permissible total weight without having to carry out a new approval.

The D-value is determined as follows:

D [kN], GA [kg], GF [kg]

Approvals / Registrations

(Modification approval in accordance with paragraph 19, section 3 StVZO in Germany)

All tow bars have been inspected and have received design approval. After being attached, the tow bars must be immediately certified as being properly attached. These modification approval certifications are carried out by the vehicle inspection authorities (in Germany: TÜV/Dekra) or inspection technicians from officially recognized supervisory organizations (in Germany: KÜS, for example). The assembly (attaching) instructions are to be presented during approval.


The ball diameter is 50 mm and corresponds to DIN 74058 and ISO 1103. The distance between the ball centre and the road surface is 350 to 420 mm when the rig is loaded (max. perm. total weight).


All WESTFALIA tow bar come equipped with the required fastening parts such as screws, shackles, etc. as well as illustrated assembly instructions. Only knowledgeable persons should assembly the tow bar. (for more on this, see "Approvals / Registration")

Assembly times

Please note that the specified assembly times only serve as a rough estimate. Depending the condition of the vehicle and/ or the capabilities and experience of the person assembling the tow bar, the actual required time may differ from the specified time. In certain circumstances, such as when an automatic CD changer has to be removed in order to install the electrical equipment, the required assembly time may become considerably longer.

Support load

The support load is the maximum permissible static vertical force that may be applied to the ball. The permissible support load corresponds to the specified support load of the given vehicle (see vehicle registration papers).

Installation instructions

The installation instructions provide general information on how to install the electrical system or attach the trailer towbar for the given vehicle.