Automotive Engineering - March 2024 - 14

ROAD
READY
2024 Lexus GX ready for off-road adventure with new platform, E-KDSS
Engineers designing
the 2024 Lexus GS,
shown here in
Overtrail trim,
wanted to leave
no doubt as to
its overlanding
bonafides.
Fuel efficiency across all trim levels of
the new GX is 17 mpg combined. There
will only be one engine option available
in the 2024 GX: Toyota's reliable 3.4-liter
V6 that produces up to 349 hp and
479 lb-ft (649 Nm). Depending on the
configuration, the 2024 GX can tow up
to 9,096 lbs (4,126 kg) in the Overtrail
trim. The new GX can go from 0-60
mph (97 kph) in 6.5 seconds.
Once Toyota finally updated the Tundra
to its third generation in 2022 after 15
years on the last-generation platform,
the next model that would logically contend
for an overhaul was the Lexus GX.
Last given a generational overhaul in
2009, the new GX has been a long time
coming. Chief engineer Koji Tsukasaki
said the updates are more than just
overdue, they're for overlanding.
" We were going to build a Lexus that
had never existed before, a true authentic
offroader that would be held as the
reference point for everything moving
forward, and we boldly changed the
positioning of the vehicle when starting
development, " Tsukasaki told SAE
Media, as translated by an interpreter
provided by Lexus.
The chunky new GX doesn't hide its
new identity. Thick lines keep the boxy
shape from being just another Land
Rover, even if that's the obvious territory
the designers were playing in. The
signature Lexus grille is still huge, but
the bottom of it has been moved up the
fascia, and a protective element was
added to the lower half to prevent
damage from road debris. The lower
section is even removable on the GX's
off-road-focused Overtrail trims. In
short, the GX's new look implies better
off-road performance, but to clinch the
deal, the engineers needed to do more
than improve the exterior.
As part of the repositioning,
Tsukasaki said, Lexus developed a
14 March 2024
AUTOMOTIVE ENGINEERING
three-prong strategy for its large SUVs.
The new GX 550 became the " true offroader, "
while the LX became the flagship
model and the TX the best option
for three-row SUV buyers. To make the
GX perform better off-road, Lexus decided
to base it on the new TGNA-F
platform. While the older Toyota
Tacoma and FJ Cruiser use the F2 variant,
the GX, the LX and the new Toyota
Tundra and Land Cruiser use the F1,
which has a higher off-road performance
capability than the F2.
" We determined at early stages that
we were going to switch from the F2 platform
to the F1 platform, the ones shared
by the Landcruiser and LX because we
wanted to create the true offroader package
of the vehicle, " Tsukasaki said.
The 2024 Lexus GX
offers 24 inches (621
mm) of articulation
thanks to its
electronic Kinetic
Dynamic Suspension
System (E-KDSS).
Off-roading with E-KDSS
Lexus' off-roading history goes back at
least to the LX 450 in the mid-1990s.
The first GX, the GX 470, debuted in
2002, and the new Kinetic Dynamic
Suspension System (KDSS) became
available for the GX in 2003. KDSS improved
stability by electronically controlling
the sway resistance of the front
and rear suspension anti-roll bars. Two
decades later, Tsukasaki and his team
improved the off-road capabilities of
the new GX by introducing a new available
feature: Electronic KDSS (E-KDSS).
The original KDSS decoupled the
swaybar stabilizers using a hydraulic
system, while E-KDSS uses electronic
control. The engineering team knew
decoupling the stabilizers was the best
way to get extra articulation because it
offered a way around the physical limits
of continuously connected stabilizers.
" Creating an electronic system allowed
us to solve one of the demerits of
BOTH IMAGES: LEXUS
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