Toyota introduced the current Lexus GX in 2010, at the same time it also redesigned the 4Runner, on which the Lexus model is based. If the GX is shifted to a unibody platform, that could mean that Toyota would do similarly with the 4Runner, or the two vehicles could diverge and the GX could assume the underpinnings of another model.
This is mere speculation, but Toyota could shift the GX to the Highlander platform that is currently shared with the Lexus RX. Since the RX is not available in a three-row model, the move would allow the GX to retain its third row as a differentiator without upsetting the successful formula of the RX, Lexus' best-seller.
Regardless of what Toyota decides to do with the GX and 4Runner, Ward's says the company is also investigating the use of turbocharged four-cylinder engines in Lexus products. Since Toyota already has one of the best engines in the world in its direct-injected 3.5-liter V6 that sits under the hood of most Lexus models, we wouldn't expect the brand to introduce a turbo four any time soon, at least not in its volume products.