With the exception of buying a house, the purchase of a motor car is the largest most people are likely to make. Consequently the buyer is naturally concerned about all the items that represent the final purchase. The car manufacturers have to try to meet many different needs from their potential customers, e.g. performance, fuel economy, range of colours available. They are also well aware of the damaging effects of poor publicity over faulty components, and consequently they aim to produce the best possible product at the price.