The relationship between movement of the accelerator pedal and system output is automatically controlled, reducing response to aggressive inputs to improve fuel economy and promote smoother driving. The load on the engine is also reduced under acceleration, which also helps improve fuel efficiency.

When the outside temperature is 20 °C (68 °F) or higher, the air conditioning system automatically selects its air recirculation mode to reduce power consumption. The blower airflow is reduced when set to “high” and operation of the supplementary electrical heating system is stopped, further cutting the amount of power used. Also, the system will not signal for an increase in engine speed to boost power when the vehicle is at idle.

Repackaging of the full hybrid system’s battery into two sections of six and 14 modules has reduced its overall size and freed up more luggage space in the boot.

Further development of the Lexus Hybrid Drive system has been revised to meet Euro V exhaust emissions standards, but with no change to the car’s performance: the combination of the 5.0-liter V8 gasoline engine and 165 kW electric motor produces a maximum 439 bhp (327 kW) and 520 N·m (383 lb-ft) of torque, giving 0 to 100 km/h acceleration in 6.3 seconds. CO₂ emissions are 219 g/km and combined cycle fuel consumption economy remains 9.3 L/100km (25.3 mpg US) (figures provisional).

The LS 600h is newly equipped with larger, 380mm ventilated front disc brakes with six-piston callipers, rotors and pads developed jointly with specialist manufacturer Brembo. The pads are designed for quieter performance with less vibration and give fade-free high-speed stopping power.