Lexus revealed at the 2013 NAIAS the latest edition of the company’s compact rear-drive sedan family that directly challenges BMW’s benchmark 3 Series. The Lexus IS serves as an entrance to Toyota’s premium brand, with the lowest average age of any car in the luxury segment, according to Lexus General Manager Mark Templin, who introduced the new car.
The car will sell in the U.S. in 2.5-L V6 IS250 and 3.5-L V6 IS350 versions, with standard rear-wheel drive and available all-wheel drive for either engine. Rear-drive IS350s get an eight-speed direct-shift Aisin automatic transmission already used on the IS F. An available F Sport package for the IS350 dresses up the IS with the bodywork similar to that of the V8 IS F. All other models use an Aisin six-speed automatic.
The all-new IS goes on sale in June, but the current-generation IS F carries over for another year.
In Japan, Europe, and other markets, the IS will be available as the IS300h, a hybrid-electric powered by a 2.5-L Atkinson-cycle four-cylinder engine. The car will deliver fuel consumption of less the 4.3 L/100 km with a total system power of 162 kW, Templin promised. Selling in markets that are sensitive to fuel consumption and CO2 emissions, Templin said the company expects more than 80% of European IS sales will be the hybrid model.
The IS300h engine’s short block is similar to that of the ES300h's but with an all-new direct-injected head, reported Paul Williamsen, Global Manager of Education and Training for Lexus.
The Drive Mode Select system lets drivers choose among four driving modes; Eco, Normal, Sport, and Sport S+ (S+ is available on the IS350 only) settings let the driver optimize fuel economy, comfort, performance, and handling to suit conditions.
The IS chassis is derived from that of the Lexus GS mid-sized sedan introduced last year, shortened for duty in the IS, Williamsen said. That means that it brings an improved multilink rear suspension featuring separate mounts for the springs and shock absorbers that frees additional space in the trunk.
The IS unibody is made with new fastening techniques for maximum stiffness. The company doesn’t release rigidity figures, but the new car is nearly as torsionally rigid as the old one, despite nearly four inches more length, Williamsen said.
Epoxy bonding is used to supplement spot welding. “There are significant increases in the strength and durability of the joints,” Williamsen said. “You get increases in torsional rigidity and improved NVH for very small marginal cost.” The sheetmetal floorpan panels where the rear suspension attaches have particularly benefited from the use of adhesive bonding in support of spot welding, he said.
The distance between spot welds in the IS varies based on an
analysis that shows where extra welds are needed and where there can be
fewer. The result is that the very same
number of spot welds can produce a stronger unibody, just by concentrating them
in stress points. Hot-stamped ultra-high-strength steel is used in roof header
rail and B-pillar for maximum strength in those areas that are critical for
Finally, Lexus has developed a technique it calls “laser screw welding.” That’s because, while it uses a laser to weld steel, it does so with so little heat that there is no heat-induced distortion of the sheetmetal, as if it were fastened with a sheetmetal screw. Lexus uses laser screw welding to weld the steel all the way around the front door openings and about half of the rear door openings, said Williamsen.
Inside the car, nearly 3 in (76 mm) of the additional length goes into rear-seat legroom for more comfortable passengers. “There is a much bigger door opening and window opening, so it is easier to get in and out of the back seat,” he said. Also, the enlarged trunk has the benefit of a folding rear seat, which splits 60/40 for carrying large objects.
A new navigation system that connects to the HD radio system shows traffic and weather data received via HD Radio with no subscription fees. IS drivers who do get stuck in traffic can pass the time listening to a Mark Levinson sound system with Harman digital amplifiers.