Energy resource and transport facility are the most important resource to define the wealth of a nation. Transport consumes the petroleum resource like petrol, diesel and gas, which are limited energy resources available in nature. For the past two decades the cost of the petroleum products are increasing and fuel saving or fuel economy are the trend in the universe. Economically consuming these resources is a way to save energy resource and wealth of the transport department and the nation. In this concern this paper concentrates on fuel consumption in a set of selected service industry transport department buses. Transport plays as a vital role in finance of the service industry. The successful functioning of the transport department and it profit limited by number of constraints. Breaking the constraints is observed as way to improve the profit by using a thinking process tool Theory Of Constraints. In this work this tool concentrates on breaking one of the selected constrains at a time instead of governing the constraints for achieving goal of maximizing profit by fuel economy.