Lexus E-CVT and hybrid

History of Lexus transmissions

The shift lever may be a simple device that helps connect car and driver, but beneath the gate lies complex mechanicals and technology that form the transmission system of your vehicle.

Without such a transmission it would not be possible for the engine or motor to transfer torque to the wheels – and there is little fun to be derived from a stationary car. What’s more, the transmission plays a vital role in generating the overall driving experience.

In view of these facts, we felt that a comprehensive, fact-filled post on the subject of transmissions was in order. Scroll down to discover what transmission types have been fitted to UK-specification Lexus models and how have these developed over the years.

Lexus Manual transmissions

The only model Lexus UK has ever specified with a manual transmission has been the IS saloon. A six-speed manual gearbox was standard equipment for all first-generation IS models, a feature that was unique within the compact executive car class at the time of its launch.

All derivatives of the second-generation IS were also equipped with a manual transmission as standard until the petrol-powered IS 250 became an automatic-only model from the 2011 model year onwards. Diesel models were only ever available with manual transmissions.

Lexus transmissions IS 200

MODEL YEAR GEARBOX GEARS DEFINING FEATURES
IS 200 1999> J160 6 Only car in class with six-speed gearbox
IS 250 2005> RA62 6 Triple-synchro mechanism from first to third
IS 220d 2006> RA63 6 Rearward driveline developed from LS 430
IS 200d 2011> RA63 6 Closely related to RA62 in IS 250

Automatic transmissions – saloon

The vast majority of Lexus models that have ever been produced feature a self-shifting gearbox of one kind or another. Before the introduction of Lexus Hybrid Drive and its associated E-CVT technology, that meant the application of traditional torque converter type automatic transmissions.

The variety within this field of transmissions is astounding, yet it is possible to apply a couple of broad facts across the entire range. First, all of these automatic transmissions were developed and produced by partner Aisin AW in Japan. All variations come under the same ‘A’ family umbrella but use additional coding to differentiate specific variations. These include the number of gears and whether the unit is designed for rear- or all-wheel drivetrains.

LS400 gearbox

MODEL YEAR GEARBOX GEARS DEFINING FEATURES
IS 200 1999> A45DE 4 ‘Intelligent’ technology learns driver’s style
IS 300 2001> A650E 5 E-shift push-button gearchange system
IS 250 2005> A960E 6 Sequential manual mode via paddle controls
IS F 2008> AA80E 8 Lock-up technology from second gear onwards
IS 250 2013> A960E 6 Faster shift speeds and downshift throttle blips
IS 200t 2015> AA81E 8 First Lexus saloon to shift in line with G-forces
MODEL YEAR GEARBOX GEARS DEFINING FEATURES
GS 300 1993> A341E 4 Electronic control, shared with the Lexus LS 400
GS 300 1998> A650E 5 Shift time reduced by 46% over outgoing A341E
GS 430 2001> A650E 5 Internals uprated to cope with torque of V8
GS 300 2005> A760E 6 Lock-up control from third through sixth
GS 430 2005> A761E 6 AI-SHIFT alters gears to match road and driver
GS 460 2008> AA80E 8 Smaller and lighter than outgoing A761E
GS 250 2012> A960E 6 Features sequential manual shift mode
GS F 2016> AA80E 8 Shifts in line with G-force and throttle data
MODEL YEAR GEARBOX GEARS DEFINING FEATURES
LS 400 1990> A341E 4 Reduces torque between gears for smoothness
LS 400 1995> A340E 4 Revised gearing, more efficient torque converter
LS 400 1998> A650E 5 Lock-up allowed in low gears, gate-type lever
LS 430 2000> A650E 5 Automatic selection of lower gears downhill
LS 430 2003> A761E 6 Closer ratios, wider range, sequential shift mode
LS 460 2007> AA80E 8 World’s first eight-speed automatic transmission

Automatic transmissions – coupe/convertible

SC 430 transmission

MODEL YEAR GEARBOX GEARS DEFINING FEATURES
IS 250C 2009> A960E 6 Faster gear changes in sequential mode
MODEL YEAR GEARBOX GEARS DEFINING FEATURES
SC 430 2001> A650E 5 Line pressure optimised to engine output
SC 430 2005> A761E 6 Closer ratios, wider range, sequential shift mode
MODEL YEAR GEARBOX GEARS DEFINING FEATURES
RC 200t 2016> AA81E 8 Directly derived from unit in RC F
RC F 2014> AA80E 8 Operates in five driver-selectable modes

Automatic transmissions – SUV

RX 300 transmission

MODEL YEAR TrANSAXLE GEARS DEFINING FEATURES
NX 200t 2015> U661F 6 Communicates with engine to calculate torque
MODEL YEAR TRANSAXLE GEARS DEFINING FEATURES
RX 300 2000> U140F 4 Transaxle with integrated front/centre diff
RX 300 2003> U151F 5 Multi-mode system offers sequential changes
RX 350 2006> U151F 5 New shift control logic reduces gear change times
RX 200t 2016> U661E 6 Reduced-friction clutch and thrust bearings

Automated sequential gearbox

As you might expect of a Lexus hypercar, the LFA’s automated sequential gearbox (ASG) is unique and unrelated to any previous Lexus model. It uses both an electric motor and advanced hydraulics to deliver the pressure and high fluid volumes needed to actuate the transmission and concentric clutch slave cylinder. Gearchange times are adjustable in seven stages – from 0.2 seconds for intense track work to 1.0 second for smooth cruising.

LFA transmission

MODEL YEAR GEARBOX GEARS DEFINING FEATURES
LFA 2011> RB60M 6 Advanced electro-hydraulic actuation

Electronically-controlled continuously variable transmissions

Electronically controlled continuously variable transmissions (E-CVT) offer an infinite number of gears within a broad range of ratios, and simultaneously handle inputs coming from the petrol engine and electric motor.

Lexus E-CVT and hybrid

The intelligence of E-CVT is evident by the fact that it selects the optimal – that is, most efficient – gear ratio for any situation by constantly analysing vehicle speed, road conditions, engine power and driver input. When that split-second passes, it moves imperceptibly to the next calculated ratio through a clever combination of planetary gears.

In order to increase the functional range of E-CVT, powerful GS 450h and LS 600h models use an additional two-stage speed reduction device (see image below) behind the output shaft of the electric motor, which allows the vehicle to offer rapid acceleration, relaxed high-speed cruising and higher top speeds. This device is directly related to the Multi Stage Hybrid system that will be found in the new Lexus LC 500h.

GS 450h transmission

Below we have defined each E-CVT as either a gearbox or transaxle. Essentially, transaxle transmissions transfer torque from one direction to another, such as from the crankshaft to the front wheels in front- and four-wheel drive models. A traditional gearbox, on the other hand, usually follows the same longitudinal direction and directs torque to a separate rear differential.

MODEL YEAR TransAXLE DEFINING FEATURES
CT 200h 2011> P410 Lightweight casing similar in size to conventional gearbox
MODEL YEAR GEARBOX DEFINING FEATURES
IS 300h 2013> L210 Sequential shift function via steering wheel paddles
MODEL YEAR GEARBOX DEFINING FEATURES
GS 450h 2006> L110 World-first E-CVT with sequential shift function
GS 450h 2012> L110 Two-stage speed reduction gears for optimal performance
GS 300h 2013> L210 Four selectable drive modes, including EV mode
MODEL YEAR GEARBOX DEFINING FEATURES
RC 300h 2016> L210 Six-step sequential gearchange function with paddles
MODEL YEAR GEARBOX DEFINING FEATURES
LS 600H 2007> L110F Two-stage speed reduction gears for optimal performance
MODEL YEAR TransAXLE DEFINING FEATURES
NX 300h 2014> P314 Torque control reduces pitching motion when off-road
NX 300h 2014> Q211 Rear traction motor with transaxle assembly
MODEL YEAR T’AXLE DEFINING FEATURES
RX 400h 2005> P310 Ball bearings and low viscosity oil reduce friction 30%
RX 400h 2005> Q211 Rear traction motor with transaxle assembly
RX 450h 2009> P313 First adoption of AI-SHIFT control on hybrid vehicle
RX 450h 2009> Q211 Rear traction motor with transaxle assembly
RX 450h 2016> P313 New water-cooled transmission oil cooler
RX 450h 2016> Q211 Rear traction motor with transaxle assembly

Multi Stage Hybrid transmission

2016.02.08

The latest transmission development from Lexus is the Multi Stage Hybrid drive system, which will make its debut in the new Lexus LC 500h. It features all the elements of a traditional full hybrid powertrain, including a 3.5-litre V6 petrol engine, a powerful electric motor and a lithium-ion battery, together with a four-speed automatic gearbox, mounted at the rear of the hybrid transmission.

Multi Stage Hybrid will provide Lexus with its first ‘M’ transmission mode on a full hybrid vehicle, allowing the driver to make direct and responsive gear changes and enjoy the most sporting and engaging drive yet from a Lexus hybrid.

To learn more about how Multi Stage Hybrid drive works, watch the video below.

Learn more: History of Lexus vehicles

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