Lexus sedans will be redone by spring 2013

Lexus sales have slipped behind BMW and Mercedes this year, but the next few years will show what kind of counterpunch Toyota's luxury brand can deliver.

The passenger-car lineup will be made over by the spring of 2013, as the GS, ES, IS and LS sedans will all be either redesigned or re-engineered.

But there are challenges. Executives and engineers say they need to remove some of the numbness from Lexus sedan handling without losing the floaty freeway ride that buyers expect.

Lexus also is unveiling a more aggressive design language that was teased at the New York auto show in April.

As far as cycle changes go, expect Lexus to follow BMW's example with a major change every three years, alternating between sheet metal and powertrain. That way there is always something new to brag about.

CT 200h: Debuted this summer.

IS: The small sedan line will be re-engineered in late 2012, based on a shrunken version of the GS platform. Expect handling refinements, but not much change in the powertrain setup. Styling will be more youthful and expressive.

The next generation is expected to get a soft-top convertible to avoid the cost and weight of the hardtop.

HS 250h: Although the plug-in Prius is moving to lithium ion batteries, the HS will stick with a nickel-metal hydride for its midcycle change in 2012. Lithium may arrive with the 2015 redesign.

ES: The midrange sedan will be redesigned in the summer of 2012. Engineers have worked on tightening the ES' handling so that it doesn't wallow so much when pushed. A hybrid option will be offered, and there's talk of a 40-mpg combined mileage. In terms of styling, the ES will get the big grille of the GS, and much more visual differentiation from the Camry platform it shares.

GS: A re-engineered version arrives in early 2012 on an updated platform shared with the IS. But it will retain the same wheelbase and width and will be barely longer overall. The suspension has been modified for a sportier ride.

Engine offerings still will include a 3.5-liter V-6, with a six-speed transmission, and the 4.6-liter V-8, but with faster acceleration and better fuel economy. A four-wheel steering system will be optional. Lexus is considering a GS-F performance edition but using hybrid power instead of a hulking V-8 to make it happen.

LS: A redesign is due in the spring of 2013 for the big flagship sedan. Weight-saving technology using premium materials is high on the priority list. As for the range-topping LS 600h, Lexus will place more emphasis on fuel economy than performance, but it will stick with a V-8 hybrid, not drop down to a V-6.

LFA: After the current batch of 500 is built, there likely will be a one-year hiatus before a roadster version is offered, probably in mid-2014.

RX: A redesign is planned for early 2014. The crossover currently rides on an ancient platform that will be updated with the new Toyota Camry/Avalon underpinnings. The hybrid battery may stay nickel-based, rather than use lithium ion, since Toyota has found packaging gains but only marginal fuel efficiency improvement from lithium.

GX: It was redesigned in the spring of 2010, so no major changes are expected.

LX: Since the incremental volume of the top-line SUV helps justify Toyota's investment in the Land Cruiser, the LX won't go away. But expect the current version to stick around longer than planned, perhaps beyond 2015.

VX: After years of study and several concept models, Lexus has delayed the idea of a seven-seat car-based crossover.