Jul 19, 2013
A few months ago we provided some simple steps to improve fuel efficiency. However, increasing and maintaining optimal fuel efficiency is far more intricate of a process than performing basic fleet maintenance and driving responsibly. The key concepts that control fuel consumption are friction, temperature and fuel/air ratio, and with over 200 moving parts in both gasoline and diesel combustion engines – not including the mechanics of power transfer – keeping each one of them at peak efficiency is hard to come by. However, there are quite a few practices that should be executed to save your business money at the pump.
Achieve Ideal Fleet Fuel Efficiency
Friction is the enemy of efficiency, and with nearly 3000 moving parts throughout the entire average vehicle, there is a lot that can hinder forward motion. To begin with point of contact, aside from proper inflation, lack of correct alignment is equivalent to dragging a vehicle as opposed to rolling smoothly. Inquire with your fleet operators regularly if they feel any pulling left or right, this is a strong indication of wheels being out of alignment; correcting this issue can increase fuel efficiency by 1 to 2 miles per gallon. A similar reduction in fuel consumption can be seen at the wheels through the other components that enable or inhibit ideal power transfer; i.e. replacing warped brake rotors, ensuring that brake pads are not rubbing, and checking to see that wheel bearings are in clean working order.
Further up the power transfer process are the mechanics that distribute the engine’s power to the wheels; i.e. differentials and transmission. Within the differential, sludgy fluid or improper fluid levels can increase friction within the structure. This issue is present with transmissions as well, both automatic and manual. However, transmissions present additional possible fuel efficiency issues through improper adjustments of the torque converter and throttle cable.
Finally, at the top of the powertrain are many parts that impact fuel efficiency. The most crucial errors occur during the explosive action of the stroke when too rich of a fuel mixture enters the cylinder, and fuel literally pours onto the road out of the exhaust. A rich mixture, i.e. too high of a fuel to air ratio, can occur due to improper maintenance of many parts; primarily O2 sensor, temperature sensor (cold engines burn more fuel), timing belt, carburetor, and air intake filter. In addition to a rich mixture, clogged intake manifolds misaligned valves, late ignition timing, dirty fuel injectors and weak spark plugs each cause fuel-injected engines to lose efficiency at an alarming rate.
By focusing on just what quick lube stations tell you is necessary for proper maintenance, a fleet can be losing thousands of dollars a year on unnecessary fuel expenses. As a fleet manager, it is important to ensure that your fleet vehicles are in full working order from the wheels to the spark plugs. Protect the bottom line and don’t make costly mistakes; utilizing a fleet card is the first step, and proper maintenance of fleet vehicles is next in line.