Lexus unveils the fourth generation of its best-selling model, the RX CUV, today at the 2015 New York International Auto Show.

Keeping the RX competitive is important to the Toyota luxury brand’s health. It accounts for three of every 10 Lexuses ever sold and roughly half the marque’s annual U.S. sales.

Global cumulative sales of the midsize RX which, along with the BMW X5 and Mercedes M-Class in the late 1990s helped usher in the luxury utility-vehicle trend, stand at 2.1 million.

“I believe the new RX will not only surprise new customers, but will also delight and satisfy our loyal customers, whose high expectations will be met by many new innovations,” Takayuki Katsuda, chief engineer-Lexus RX, says in a statement.

Lexus completely revised the RX’s front end, giving it the more aggressive character of recent Lexus designs. The brand’s signature spindle grille is a key feature of the new look, as are triple L-shaped headlamps.

LED fog lamps and daytime running lights enhance the vehicle’s “sophisticated and advanced look,” Lexus says.

A sharp character line and flowing roofline not only are for appearance, but also keep the RX planted at high speeds while limiting wind noise, Lexus says.

A floating roofline is achieved via a blacked-out C-pillar, a first for Lexus.

The RX will offer 20-in. wheels for the first time. The wheels are aluminum with inserts that color-match the body. Standard wheels are 18 ins.

L-shaped LED taillights wrap around the sides of the vehicle to give it a wider look.

The non-hybrid RX has integrated dual exhaust pipes.

Yamaha laser-cut wood trim is available in the RX’s interior, which Lexus says has an overall warm feel.

Interior details are scarce, but Lexus notes the shifter has been moved away from the front of the instrument panel to increase driver space.

A heads-up display will be available, as will a 12.3-in. (31-cm) display screen atop the center stack.

Rear knee and leg room is increased from the outgoing RX, and rear passengers now have the option of heated outboard seats.

A power panorama moonroof is available, as is a rear-seat entertainment system with 11.6-in. (29-cm) dual screens in the back of front head restraints.

The ’16 RX is roughly 5 ins. (127 mm) longer than the ’15 model, with a 2-in. (108-mm) longer wheelbase.

The RX 350 still is powered by a 3.5L V-6 but gets increased horsepower for ’16 thanks to the addition of direct injection and an 8-speed automatic transmission.

The RX now peaks at 300 hp, up from 270 hp in the ’15 model, which has a 6-speed automatic.

The ’16 RX 450h hybrid also is expected to produce 300 hp, with its Atkinson-cycle 3.5L V-6 mated to an electric motor/generator.

Lexus says it has “fortified” the RX’s chassis for better straight-line stability and control through turns.

The CUV’s body also is stiffer to improve handling as well as reduce engine and road noise that may infiltrate the cabin.

The RX’s suspension, MacPherson struts in the front and a double wishbone in the rear, is said to be tweaked for improved ride and handling.

Lexus will offer an adaptive variable suspension for the first time on the RX, which can adjust shock absorber damping for a better ride and less body lean in corners.

The ’16 RX will ride on Michelin Premier tires with the supplier’s EverGrip technology, which features grooves that widen and open over time.

As announced this past Monday, the RX will offer a new low-cost automatic braking package, Lexus Safety System+, as part of Toyota’s effort to reduce vehicle collisions.

Lexus Safety System+ has pre-collision braking, lane-departure alert, automatic high beam headlights, lane-keep assist and adaptive cruise control.

As it has with most recent releases, Lexus will offer an F Sport package on the redesigned RX for both conventional and hybrid models.

While F Sport features largely are visual (a unique mesh grille, graphite-finish 20-in. alloy wheels, perforated leather trim), the athletic grade will get an active stabilizer system to keep the vehicle flat in corners. The adaptive variable suspension will be standard on the RX F Sport.

While the current RX is six years old, it has shown remarkable staying power. Sales last year rose 3.4% to 107,490 units, WardsAuto data shows.

The new RX goes on sale in the U.S. in the fourth quarter.