Underway, the QX56 responds to its 5.6-liter V8 engine. Full-throttle acceleration with two aboard and no cargo is solid if not spectacular, as this engine is tuned for low-end torque, load-hauling and trailer-towing, not high-rpm wailing. It sounds powerful, and it is, but this truck weighs almost 5900 pounds at the curb.
The ride is supremely cushy and quiet, but the body's movements over the suspension are well controlled and there is very little body roll or wallow, even in fast corners, owing to the hydraulic body motion control system. The steering ratio and power assist are perfect for a long, tall, heavy vehicle like this one.
The brakes are powerful and progressive even when soaking wet (we drove nearly the entire day in a raging thunderstorm). The Intelligent Braking System uses sonar ranging to stop the QX56 all by itself as it approaches another stopped vehicle, which is a bit disconcerting at first, but once you get used to it, it's a nice thing to have in stop-and-go traffic, and it's part of the Technology Package.