The main procedure for servicing the body is washing with plenty of water (from a hose), which allows you to remove all the dirt and solid particles from the car. It is important to wash them off so that the gravel does not scratch the paint. The wheel arches and the underbody also need to be washed - the dirt accumulated on them absorbs moisture from the environment, which increases the risk of corrosion. It is easiest to clean the underbody and arches in rainy weather, when the mud build-up has become soaked and soft. Sometimes in rainy weather the underbody cleans itself, and this is a good time for inspection.
Periodically (except for vehicles with a protective wax coating on the underside) clean the underbody with steam. Then, perform a full inspection of the body, noting any areas that require minor repairs. Steam cleaning is available at many service stations and is necessary to remove oily deposits. If steam cleaning is not available, there are special solvents available for removing such deposits. Apply the solvent with a brush, then simply rinse off the dirt with a stream of water. This method should also not be used on cars with a protective wax layer on the underbody, otherwise this layer will be removed. Such cars should undergo an annual inspection, preferably in the fall, during which the underbody should be washed and the protective layer, if damaged, restored. It is recommended to inject the same protective wax composition into the door panels, sills and other cavities of the body as additional protection against corrosion.
After washing painted surfaces, buff them with a chamois to restore their shine. Applying a thin layer of wax polish will provide additional protection against airborne chemical pollutants. If the paint is dull or oxidized, use a special cleaner/polish combination to restore the shine. This requires some effort, but only occurs if regular washing has been neglected. Metallic paint requires careful handling - use a special non-abrasive cleaner to avoid damaging the paint. Make sure that door drains and drain pipes are not clogged. Windshields and windows should be washed periodically with a glass cleaner. Never apply wax or chrome polish to glass.
[Text provided by an online resource: www.RenaultBook.ru]