Fuel Economy and Heavy Vehicle Wheel Alignment

Have you ever thought that there is much more to achieving efficient fuel economy than just considering how hard you press your speed pedal? A vehicle is a system and for it to function at its peak, each subsystem must be maintained at its default settings. Some subsystems, such as the transmission and the engine size, have large effects on fuel efficiency, while others, such as tires, contribute less. If you are looking to save every drop of fuel, especially in heavy commercial vehicles, how much each subsystem contributes to fuel economy matters a lot. Here are a few tips and tricks on how to maintain good fuel economy by ensuring good wheel alignment.

  1. Caster: Caster adjustment is the industry setting that allows the wheels to automatically return to the center position when completing a turn. Therefore, having less camber will make the vehicle twitchy, especially at higher speeds. It becomes difficult to control the vehicle as it darts across the road and fails to return to the center position. Apart from this being a dangerous driving situation, it also hurts the fuel efficiency of the vehicle, as weaving slows the car down, resulting in consumption of more fuel.
  2. Toe: This is the most important aspect of heavy vehicle wheel alignment in terms of fuel efficiency. Toe is the angle derived from viewing the inward or outward direction of the tires from a top-down position. It is easier to think that the tires must be set to point towards the center for a vehicle to drive straight. However, pointing the tires at an angle, either inwards or outwards, is critical for stability and performance. Toe-out is common in heavy vehicles in order to support wide or heavy loads. Improper toe setting negatively affects fuel economy; it can make the tires to work too hard against each other, or force the car to pull towards one side, situations that will slow the vehicle down and, thereby, require more fuel to maintain movement.
  3. Rear Axle Alignment: The alignment of rear axles in heavy vehicles is necessary to keep tires and wheels in the optimum working conditions. Have you ever followed a track that is slightly twisted sideways as it moves down the road? This is exactly what happens in a vehicle with a misaligned rear axle. A properly aligned rear axle should have its center-line set exactly perpendicular to the chassis center-line. Misalignment results in excessive tire-to-road drag, which in turn, results in less than optimum fuel consumption.

Heavy trailers and trucks should regularly be checked for abnormal tire wears, and be adjusted periodically for optimum performance. Minor shifts from the default settings cause more drag and higher tire rolling resistance, which accounts for a segment of fuel consumption. Proper wheel alignment helps reduce rolling resistance and, therefore, results in less fuel consumption.