Notes on installing a trailer hitch - AH31.10-P-1000-02SX

MODEL 221 

Fig 1: Identifying Trailer Hitch

Courtesy of MERCEDES-BENZ USA

The control cable must be hung in the operating lever before the transport lock between the crossmember and swivel ball neck is removed. Otherwise the system locks and cannot be unlocked. The ball neck snaps into its two end positions and can only be operated using the cable at the release lever.

In export countries the respective licensing provisions or legal requirements for the installation of a trailer hitch must be observed.

On all areas in which the trailer hitch comes into contact with the body, the body sealing compound and the underbody coating are to be removed. The mounting points should then be cleaned with a commercially available cleaning agent. Apply anticorrosion paint to bare-metal areas of the body.

Trailer hitches are homologated safety-related parts. Their installation on the vehicle is to be carried out exclusively by trained, professional technicians. Trailer couplings, which are damaged because of an accident, bottoming or being run into from behind, must be replaced; subsequent alterations such as bending, mechanically processing, and welding are not permitted.

The coupling ball must have a minimum diameter of 49 mm at all points, measured using a caliper gauge.

The ball must be greased before use to reduce wear. Advise the customer accordingly.

On trailers with an anti-swerve device  it is not necessary to grease the ball (see trailer instructions). Advise the customer accordingly.

The customer should be asked to read the chapters entitled "trailer hitch" and "Trailer operation" in the vehicle's operating instructions.

The customer should be advised to install a more powerful battery (at least 70Ah).