Part of preparing the site for a road is moving dirt, and one of the primary types of equipment used to move dirt is the loader. A recent technological advancement on Caterpiller’s five midsize wheel loaders is a new engine idle software package to help maximize fuel efficiency and allow flexibility in managing work idle speeds. The Engine Idle Management System (EIMS) comes with four idle control modes: hibernate, work, low-voltage and warm-up. Hibernate mode is set at a factory default of 600 rpm and is engaged when the transmission is in neutral and the parking brake is set. It automatically resets to working idle with a shift of the machine, release of the parking brake or push of the governor pedal. Hibernate mode can conserve fuel by 40-45%, especially in applications where machines spend a lot of time idling. The EIMS also has warm-up mode for cold-weather operations and low-voltage mode to prevent battery discharge. The warm-up mode increases the low-idle engine speed to 1,100 rpm to generate additional engine heat in cold weather. As for the low-voltage mode, when the battery voltage drops below a set point, the engine speed will ramp up to 1,100 rpm to charge the battery. Low-voltage mode is especially useful when using lighting or air conditioning.