Perhaps the most significant technological feature of the new 3.5L V-6 is the adaptation of variable valve timing – a first for cam-in-block engines. The system incorporates a vane-type camshaft phaser that changes the angular orientation of the camshaft, thereby adjusting the timing of the intake and exhaust valves to optimize performance and economy, and helping lower emissions. It offers infinitely variable valve timing in relation to the crankshaft. The cam phasing creates "dual equal" valve timing adjustments. In other words, the intake valves and exhaust valves are varied at the same time and at the same rate. The cam phaser vane is attached to the camshaft on the front journal – a technique made easier by the award-winning "assembled-camshaft" design pioneered by General Motors. With this design, separate camshaft lobes are installed on a hollow camshaft tube rather than the traditional method of grinding a camshaft from a single piece of stock. The cam position sensor reads a new cam target ring, with four segments that increases the accuracy of the position readings. Hydraulic roller lifters actuate the valves via pushrods.

The variable intake manifold is an engine feature usually found only on high-cost, premium European performance cars, but the new manifold design is standard with the 3.9L V-6. The active air intake optimizes incoming airflow through a valve in the intake manifold. The valve creates longer or shorter intake tracts that correspond to desired engine-performance parameters. At low engine speeds, the valve creates a longer path for intake air, enhancing combustion efficiency and torque output. At higher engine speeds, the valve opens, creating a shorter air path for maximum power production.