Over the past six months the decision processes involved when buying a car have changed, according to a poll.
The survey published by AA Personal Loans shows that it is now car running costs - such as fuel economy and the cost of car insurance premiums - rather than reliability that is the most important factor influencing people buying vehicles.
In March 2008, 28% felt that fuel economy was important, but this figure has risen to 45%. Meanwhile, the number seeing reliability as important has fallen from 33% to 24%.
The second most important reason for changing cars now is that the current model is too old and needs replacing.
In the reasons-to-buy table reliability is now third. The fourth reason is the need for a new car to make longer journeys, followed by desire to buy a "green" car.
The company's chief executive, Mark Huggins, said: "Despite falling petrol costs, our first car purchase index shows that the current financial climate is making people reconsider their options when buying a car, and looking for something cheaper to run is a good way for a family to economise."
The survey was based on responses from 8,000 AA members.
© Press Association 2008