The addition of GS 250 will see Australian Lexus customers offered three powertrain variants, with GS 350 and 450h already confirmed.
Headlining the range will be a new 252kW, direct and port injected, Atkinson cycle quad cam 3.5-litre V6 hybrid in the GS 450h, which is expected to be 20 per cent more fuel efficient that the outgoing hybrid.
GS 450h will sprint from 0 - 100km/h in 5.9 seconds and it consumes 6.2litres/`00km.
New to the range and replacing the 183kW 3.0-litre V6 is a new 3.5-litre, quad cam V6 featuring direct and port injection developing 233kW.
Despite its larger capacity, the new-to-GS 350 engine will use less fuel than the outgoing model and rocket to 100km/h in 6.0 seconds.
Now confirmed for Australia and providing greater choice for new GS customers is a 2.5- litre quad-cam V6, developing 154kW of power.
The new GS 250 model will accelerate to 100km/h in 8.6 seconds and features an electronically controlled six-speed sequential transmission with paddle shift and throttle blipping on downshift in manual mode.
All models will be available in F Sport guise, offering greater dynamic and visual enhancements over standard models.
The all-new GS range will launch in Australia in the second quarter of 2012.
Prices and model range will be available closer to launch.