There are a number of points which need to be checked before towing a trailer or caravan.
Trailer weights
Never exceed the maximum permitted trailer weights link►.
If you do not load the trailer up to the maximum permitted trailer weight, you can then climb correspondingly steeper gradients.
The maximum trailer weights listed are only applicable for altitudes up to 1000 m above sea level. With increasing altitude the engine power and therefore the car s climbing ability are impaired because of the reduced air density, so the maximum trailer weight has to be reduced accordingly. The weight of the car and trailer must be reduced by about 10% for every further 1000 m (or part thereof). This figure refers to the combined weight of the (loaded) vehicle and (loaded) trailer.
Draw bar weight
The vertical load exerted by the trailer drawbar on the ball joint of the towing bracket must not exceed the maximum weight specification.
If the draw bar weight is too low, the trailer’s handling will be affected. In the interests of road safety, we recommend that you always use the maximum draw bar weight without exceeding it. You can achieve this, for example, by distributing the trailer load correctly.
You can determine the draw bar weight e.g. using bathroom scales or a public weighing station.
You can find the maximum draw bar weight for your vehicle in the registration documents or on link►.
Distributing the load
The vehicle’s handling can be impaired if the load is poorly distributed. Load the trailer according to the following criteria as far as possible:
- Objects should preferably be stowed in the luggage compartment. The vehicle load should be as heavy as possible and the trailer load as light as possible.
- Distribute loads in the trailer so that heavy objects are as near to the axle as possible.
- Objects must be secured to prevent them from sliding about.
- Where possible, operate the trailer with the maximum permitted draw bar weight.
Engine cooling system
Towing a trailer or caravan places a heavier load on the engine and cooling system. Please make sure that there is enough coolant in the cooling system.
Tyres
Check the tyre pressures on your car, and adjust for “full load” conditions (refer to the sticker listing the tyre pressures) link►.
It may also be necessary to adjust the tyre pressures on the trailer according to the recommendations of the trailer manufacturer.
At low outside temperatures, both the towing vehicle and the trailer should be fitted with winter tyres.
Exterior mirrors
Check whether you can see enough of the road behind the trailer with the standard exterior mirrors. If this is not the case you should have additional mirrors fitted. Adjust the mirrors to give sufficient vision to the rear.
Exterior lights
Before starting a journey, check all the trailer lights with the trailer hitched up.
The headlight range control automatically adjusts the range of the headlight beam.
Power supply
When you switch off the ignition, the power supply to the trailer is not interrupted as long as the energy management system does not intervene link►.
Stabiliser
Swaying and pitching can be reduced by attaching an extra stabiliser to the trailer. It should have friction linings at the sides to prevent excessive wear. Degrease and clean the ball joint before using a stabiliser. The stabiliser can be purchased and installed at a qualified workshop.
Clean and grease the ball joint before using a trailer without a stabiliser.
Towing bracket
Check that the coupling meets the relevant country-specific regulations and is not worn.
Trailer brake
If your trailer has an overrun brake, it must be correctly adjusted and function correctly.
Air suspension
Applies to: vehicles with air suspension
The air suspension must be set to the normal height level before adjusting the draw bar weight and before hitching up the trailer ►, link►.
On vehicles with a factory-fitted towing bracket, the air suspension is automatically set to towing mode when you connect the trailer cable to the socket.
On vehicles with a retrofitted towing bracket, you must switch the air suspension to towing mode manually. Select the following on the infotainment system: MENU button > Car > left control button > Vehicle settings
> Air suspension: trailer. You should deactivate the mode again when the trailer is unhitched.
You can also deactivate the towing mode manually during a journey, e.g. if you are using a bicycle rack.
If you have to drive on a rough surface, you can raise the vehicle again after hitching up the trailer and adjusting the draw bar weight.
Applies to: vehicles with air suspension
- The height of the vehicle can change as a result of variations in temperature and loading.
- Set the air suspension to the normal height level; otherwise the draw bar weight specification for your vehicle will no longer apply.
Retrofitted parts, in particular attachments fitted to the ball joint of the towing bracket, can cause damage. If any damage occurs, you should have the equipment checked by a qualified workshop.
Note
- Use wheel chocks when parking on a gradient if the trailer is carrying a load.
- We recommend having the car serviced between the normal inspection intervals if it used frequently for towing a trailer.
- Avoid towing a trailer or caravan while running the vehicle in.