Produced by Lexus, the luxury division of the Japanese automaker Toyota, the XF40 served as the flagship vehicle of the former's lineup from 2006 until production ended in 2017.

The second—and most significant—occurred in 2013, including noteworthy upgrades to incorporate the company's corporate fascia, comprising the implementation of the "spindle" grille and prominently redesigned headlamps.

1" vehicle; alternatively called the "Circle-F" project), a clandestine initiative aimed at creating a world-class luxury sedan for the global market.

[14] The development of the fourth generation of the LS began around 2001,[15] as Lexus was shifting its design strategy towards a more diversified product lineup, with new-vehicle launches largely focused on global markets.

The design features body forms running the length of the car, with wheel arches, arrow-shaped chrome trim, a grille set slightly below the level of the headlamps, and a fastback rear decklid.

[26] Compared to the previous generation LS, the forward and aft coefficient of lift was reduced to 0.02 and 0.01, respectively, while aerodynamic drag remained the same (Cd 0.26).

[30][31] Both front and rear window frames are each constructed from a single die-cast zinc piece, plated in chrome and then polished by hand.

[29] Interior features include a 19-speaker Mark Levinson Reference Surround Sound System, Gracenote, and a 30 GB HDD with room for 2,000 songs.

Japanese market LS sedans also feature MiniDisc compatibility, television reception, onboard security surveillance cameras, and remote cellphone access.

When activated, the LDW system will issue an audiovisual warning and LK will apply a brief corrective steering response when veering motion is detected.

[40] Debuted on the fourth generation Lexus LS, the next-generation Pre-Crash System (Pre-Collision in the U.S.) offers forward and rear protection.

The Frontal Pre-Crash system will activate a warning buzzer and red dash lights to alert the driver if a potential hazard is detected in the vehicle's path.

[43] For 2010, the LS hybrid further incorporated an all-TFT instrument panel display,[44] which featured the addition of a night vision capability with pedestrian detection.

An Emergency Steering Assist system acts to minimize body roll and improve vehicle responsiveness in sudden maneuvers.

This system reduces the steering gear ratio and prompts the suspension to adopt stiffer settings,[39] helping make emergency maneuvers more stable and controlled.

[52] Also debuting in late 2009 for the 2010 model year was the revised LS hybrids, including refreshed front and rear fascias, a four-bar grille, the addition of side mirror turn signals, and new wheel designs.

The substantial update incorporates the new Lexus corporate fascia, comprising the "spindle" grill and consequently sees the fitment of a redesigned hood, reshaped front fenders and headlamps, plus a new bumper.

Introduced at the 2006 North American International Auto Show, the redesigned LS was based on the LF-Sh concept vehicle and used an all-new platform.

[60] To increase rigidity and lower unsprung weight, forged aluminum was used for the suspension links, front steering knuckles, and rear hub carriers.

[61][62] along with a single-piece hollow die-cast aluminum front subframe with machined mounting points,[61] and approximately half of the body used high-tensile steel.

[68] Both models are equipped with Lexus Hybrid Drive, featuring a 5.0 L 2UR-FSE V8 engine mated to two electric motors with nickel-metal hydride battery packs.

[71] European emissions standards testing has listed the LS 600h L's CO2 emissions at 219g/km, and the vehicle is listed under the United Kingdom's Vehicle Excise Duty tax band F.[72] According to EPA testing, the LS 600h L earns an energy impact score of 16.3 barrels of petroleum gasoline per year, with a carbon footprint of 8.7 tons of CO2 emitted per year.

Hybrid-only features included the first production low beam LED headlights in the U.S. market,[74] a leather-trimmed dash, and blue-tinted badging;[74] the standard SmartAccess key fob can also be substituted with a 3.35 mm (0.132 in) thick wallet-sized "smart card".

When the LS hybrid originally went on sale in July 2007, Lexus initially targeted 7,000 total units worldwide for the first year,[80] and 2,000 annually in other markets.

[67] Ward's Auto and other media outlets reported that the Lexus LS 600h first year's (2007) allocation was entirely sold out and that there was a one-year backorder as a result.

[88] These special models came in an exclusive Truffle Mica color with Alabaster interior, with chrome wheels and a customized Italian leather luggage set.

[92] At 2007's Salone del Mobile, Lexus presented an "Invisible Garden" exhibition at the city's Zona Tortona featuring a frosted LS 600h hybrid model.

[94] The LS 600h L Landaulet's rear cabin featured a transparent bubble roof with no additional reinforcement, and the vehicle received a bespoke, water-based blue livery.

At the 2007 New York International Auto Show, the LS 460 received the World Car of the Year award, selected by automotive journalists from twenty-two countries.

[111] The LS 600h L has also received the Canadian Automobile Association's CAA Pyramid Award for Safety Innovation,[112] and has been named to Forbes' list of the Top Ten Least-Polluting Luxury Cars.