According to latest reports, the new RX will also get an alloy bonnet, tailgate and door skins to help it shed some weight.
Moving to aluminium for some body parts will help pare back its bulk, which will also improve performance as well as fuel economy.
On the flipside, aluminium is harder to manufacture panels from and is also costlier than steel.
The new RX range is expected to make its debut in the latter half of 2015 and go on sale as a 2016 model.
The current four-cylinder, six-cylinder and hybrid powertrain options are expected to continue, though the NX 200t's turbo four-pot could find its way under the RX's alloy bonnet.
An eight-speed automatic will likely replace the current six-speed slushbox, and a seven-seat configuration may be offered for the first time in the RX's history.
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