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For 1990-2009 cars only

PAINT/CARE OF CAR FINISHES ALL VEHICLES AFFECTED

VEHICLES AFFECTED: ALL MODELS

Do you ever have customers ask, "What's the best way to look after my paint job?" Well, here are a few points to consider.

Modern car finishes are very resistant, to all normal forms of atmospheric attack provided a simple maintenance procedure is followed. They will retain their colour, gloss and protective qualities throughout the life of the vehicle.

However, car finishes are not that resistant to some foreign material, deposits such as calcium chloride and other salts and chemicals from industrial chimneys.

WASHING:

Many contaminants which will attack a paint film are water soluble. They can be removed before any harm is done by washing with plenty of water and a few drops of detergent. Frequent washing is the best safeguard against unseen contaminants. At the same time it ensures the regular removal of dirt. Dust and traffic film. Washing with warm water and detergent will remove the gummy deposits that fall from trees in the summer months. Silicone and wax removers will remove tar or grease type stains, as well as other contaminants.

POLISHING:

A car finish will eventually lose some of its gloss and an accumulation of traffic film will occur but normal washing and a polish will restore the original lustre of the paint film.

High gloss and some added protection against contamination can be gained by wax polishing. But it should be remembered that a wax polish can only be used successfully on a clean surface. The previous application must be removed with silicone and wax remover. Usually a twice a year application of a good quality polish is recommended.

CONTAMINATION:

The amount of contamination a car is exposed to will vary according to climate location and existing conditions with, for example, manufacturing centres more open to contamination rural areas.

Contamination may come from a number of sources such as:

(A) Air borne "industrial fallout" and "acid rain". (B) The vehicle itself. (C) Highways and surrounding areas.

WATER DAMAGE:

Water left lying on the surface for long periods of time can have a detrimental effect on the paint coating. The resulting contamination would be water spotting and will not be visible immediately. This can occur if the car is kept in a poorly ventilated garage. Without adequate garage ventilation, it is preferable to keep the car outside under a carport.

INDUSTRIAL FALLOUT:

The term industrial fallout was first used to describe the minute particles discharged from the smokestacks of smelters and other manufacturing plants. Of course it is in no way confined to these areas. Strong winds can carry the particles for many miles and in the presence of moisture, and particularly if they are the least bit magnetic they can easily become attached to the paint surface. Soon they may discolour or pit the surface of the paint. If allowed to remain they may penetrate right down to the primer or even to the metal itself.

Regular and frequent washing is the best safeguard against attack. Where there is light contamination and the particles are not embedded in the film, they can be removed by compounding and polishing. Severe contamination may acquire the use of chemical cleaners or in extreme cases the repainting of the car.

ACID RAIN:

"Acid Rain" is the term given to rain containing particles from manufacturing and chemical industries. Some of the particles may be acidic or alkaline the presence of water, e.g. sulphur dioxide will dissolve in water to give an acidic solution, while a mixture of cement dust and water is strongly alkaline. Such particles will attack paint films. The attack may take the form of discoloured spots due to attack on the pigment. For example, some reds will develop a blue tone if attacked by acids and a brown discolouration if attacked by alkali.

Some pigments are more sensitive to attack than others. The aluminum flake in metallic paints is particularly prone to attack by both acid and alkali. The use of a clear topcoat such as polyurethane clearcoat, will help shield the aluminum from the contaminant.

Polyurethane enamels have the best chemical resistance of all refinish topcoats.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.