Nissan applied seemingly all available technology to improve the competitive position of its new Infiniti QX56 vs. the segment-leading (in sales) Cadillac Escalade, with an upgraded engine, transmission, frame, body structure, and electronic safety and convenience equipment.
This thorough revamp was worthwhile because, although the segment has declined in popularity, Americans still buy more than a quarter million full-size SUVs every year, pointed out Larry Dominique, Vice President of Product Planning for Nissan North America Inc. “We think we have upside potential in this market,” he said.
Some of that new upside evidently comes from following the old “longer, lower, wider,” dictum, with the new model measuring 1.4 in (36 mm) longer, 3.8 in (97 mm) lower, and 1.1 in (28 mm) wider than before.
The QX’s updated version of the corporate 5.6-L V8 engine adds direct gasoline injection and variable valve timing and lift on the intake side of the double overhead cam unit, boosting power to 400 hp (298 kW) and torque to 413 lb·ft (560 N·m). The previous engine was rated 320 hp (239 kW) and 393 lb·ft (533 N·m).
The stronger engine enjoys additional ratios in its automatic transmission, which is now a seven-speed unit up from five. The new unit not only has a wider spread of ratios but also features adaptive programming that alters shifting according to the driver’s preference.
If not, there is also a manual-shift mode which, along with the Hill Start Assist feature, should permit the driver to maintain better control of the vehicle when using its 8500-lb towing capacity. The new transmission also benefits from the use of a variable lockup torque converter and a fluid warmer, which is said to make it more efficient after cold start-up. The result is expected to be a 10% improvement in fuel efficiency.
The improved powertrain bolts into a new foundation, with a stiffer frame that has wider-section side rails, stronger attachments for crossmembers, and an integrated trailer hitch. The body attaches with stronger mounting points, and the cabin features a strengthened ring structure surrounding the tailgate. Additional high-strength steel is used in the body and frame, contributing to the QX’s 100-lb (45-kg) mass reduction compared to the previous model, reported Dominique.
The body has been smoothed and beveled to trim the QX’s drag coefficient to 0.37 with zero lift. A front air dam, rear spoiler, and revised side-view mirrors also contribute to that low drag number.
Optimized wheel castings whittled mass from the aluminum wheels, so that the 20-in wheels weigh less than those on the old model and the newly available 22-in units weigh no more than the old 20s, he said.
The Hydraulic Body Motion Control system, which is part of the Deluxe Touring Package, employs linked hydraulic cylinders in the shock absorbers that move fluid between the left and right sides of the vehicle through weight transfer while driving. This decouples roll damping from bump damping, allowing bump absorption to be softer than would otherwise be possible and giving the QX a better ride without letting it wallow in turns.
The QX is available in both rear- and four-wheel-drive configurations. The four-wheel-drive system can shift up to half the engine’s torque to the front wheels, depending on available traction.
The QX56 should reach dealers this summer.