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.
|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.
|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|
|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|
|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
|IS 250C||2009>||A960E||6||Faster gear changes in sequential mode|
|SC 430||2001>||A650E||5||Line pressure optimised to engine output|
|SC 430||2005>||A761E||6||Closer ratios, wider range, sequential shift mode|
|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
|NX 200t||2015>||U661F||6||Communicates with engine to calculate torque|
|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||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.
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.
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.
|CT 200h||2011>||P410||Lightweight casing similar in size to conventional gearbox|
|IS 300h||2013>||L210||Sequential shift function via steering wheel paddles|
|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|
|RC 300h||2016>||L210||Six-step sequential gearchange function with paddles|
|LS 600H||2007>||L110F||Two-stage speed reduction gears for optimal performance|
|NX 300h||2014>||P314||Torque control reduces pitching motion when off-road|
|NX 300h||2014>||Q211||Rear traction motor with transaxle assembly|
|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
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