Sales of Toyota’s large SUVs and pickups may have tanked in the U.S. but the carmaker’s luxury division, Lexus, is doing even worse, with July sales levels diving 25% from levels just one year ago. Part of the problem is that Lexus’ sales are heavily skewed towards its luxury SUV models such as the RX and LX lines at a time when the market is moving away from those vehicles. Another key problem is that Lexus’ sedan lineup is starting to show its age against many of its rivals.

To invigorate its aging lineup, Lexus is planning several significant updates in the coming years including the addition of an all-new model. The first new model will be the redesigned RX range, which is expected to launch early next year as a 2010 model. The new RX will be slightly bigger than the current model and will include a third-row seating option for the first time. There will be several new hybrid versions too, as Toyota has already filed trademarks on the RX 430h, RX 440h and RX 450h titles, reports Automotive News.

In 2010 Lexus is expected to launch its new LF-A supercar and will follow it soon after with a flagship roadster variant. Both cars will feature a high-revving V10 engine with more than 500hp (373kW) and a price tag in excess of $160,000.

After the LF-A, Lexus will debut its first dedicated hybrid model. Based loosely on the next-generation Toyota Prius, the new model will arrive in late 2010 and feature a four-cylinder petrol engine mated to the latest iteration of Toyota’s Hybrid Synergy Drive system. Around this time, Lexus is also expected to launch convertible and coupe versions of the IS.

The next-generation ES sedan will be updated along with the new Toyota Camry and is not due to appear until 2011. That same year will also see the introduction of the next-generation GS range. A high-performance version of the current GS, meanwhile, has reportedly been put on hold as officials wait to see if the economy improves.

Unlikely to see a replacement is the current SC430 convertible and GX crossover. Both cars have seen sales slump and there are currently no plans for replacement models. Finally, Lexus is expected to introduce a new crossover model based on the Toyota Rav4 platform for Japanese and European markets, but there are currently no plans to bring this model to the North America. This could change, however, if fuel prices remain where they are or go even higher.