If the vehicle has a 5.3L V8 engine, it has Active Fuel Management™. This system allows the engine to operate on either all or half of its cylinders, depending on driving conditions.

When less power is required, such as cruising at a constant vehicle speed, the system will operate in the half cylinder mode, allowing the vehicle to achieve better fuel economy. When greater power is required, such as accelerating from a stop, passing, or merging onto a freeway, the system will maintain full-cylinder operation.