Toyota 4WD review (2)

Eugenio,77
mail@toyota-club.net
© Toyota-Club.Net
Feb 2004 - Dec 2022


Part 1. Initially FF models with automatic transmissions
Part 2. Initially FR models with automatic transmissions
Part 3. Initially FF models with manual transmissions

2.1. Full-time all-wheel drive

2.1.1. Multi-Mode type

Full-time four-wheel drive with the ability to disconnect front wheels, asymmetrical center differential with a forced locking or Torsen LSD.
There is disconnected front-wheel drive system with ADD in this scheme, but the transfer obtain asymmetrical differential (torque distribution between front and rear wheels - 40:60). So, 4WD can be used permamently in all conditions, and front drive may be disconnected for the fuel economy only.

H2↔H4 - speed below 80 km/h with accelerator released, not engage during slipping.
H4H→H4L - at speed below 100 km/h, not engage during slipping.
H4L↔L4L - when the vehicle is stationary and at "N" range of transmission.


H2↔H4 - at speed below 100 km/h (if temperature below -15°C - 70 km/h).
H4↔L4 - when the vehicle is stationary and at "N" range of transmission.
Center differential lock - at speed below 100 km/h


ModelProductionTransmissionDifferential locking
4Runner 1851998-2002A340Fcenter - mechanical, rear - mechanical (opt.)
4Runner 2152002-2009A340F,A750Fcenter - mechanical, rear - mechanical (opt.)
HiLux Surf 1851995-2002A340Fcenter - mechanical, rear - LSD (opt.)
HiLux Surf 2152002-2009A343F,A750Fcenter - mechanical, rear - LSD (opt.)
Sequoia 452000-2007A340F,A750Fcenter - mechanical (-2004) / Torsen + mechanical (2004-)
Sequoia 652007-2022A750F,A760F,AB60Fcenter - Torsen + mechanical

2.1.2. Full-Time Visc type

Full-time four wheel drive, with a symmetrical center differential, locking by viscous coupling
The basic scheme for vans with the center differential, partially locking by viscous coupling.

"+" Full-time four-wheel drive, no necessary to control.
"-" Low efficiency of viscous coupling, no low range in transfer.

Detailed description - "Toyota all-wheel drive. Fulltime-Visc"



ModelProductionTransmissionDifferential locking
HiAce KZH10#..12#1993-1995A340F+TF1BVcenter - viscous coupling, rear - LSD (opt.)
HiAce/RegiusAce 1001995-2004A45DF,A340F+TF1BVcenter - viscous coupling, rear - LSD (opt.)
HiAce/RegiusAce 2002004-..A340F,A343F+TF1BVcenter - viscous coupling, rear - LSD (opt.)
Regius/Touring HiAce 401997-2004A43DF,A45DF,A343F+ TF1BVcenter - viscous coupling, rear - LSD (opt.)
Granvia/Grand HiAce 10..201995-2004A343F+ TF1BVcenter - viscous coupling, rear - LSD (opt.)
Estima 201990-1999A46DF,A340F+ TF1AVcenter - viscous coupling
Estima Emina/Lucida 201992-1999A43DF,A45DF,A46DF+ TF1AVcenter - viscous coupling
LiteAce/TownAce 851999-2007A44DF+ TF1BVcenter - viscous coupling
LiteAce/TownAce Noah 501996-2007A44DF,A45DF+ TF1BVcenter - viscous coupling
Dyna Y2##2001-..A442F,A443F,A340F,AC60Fcenter - viscous coupling

2.1.3. Full-Time H (i-Four) type

Full-time four wheel drive, with asymmetrical center differential, locking by hydromechanical clutch
Toyota top-model's have an advanced scheme of 4WD, similar to principle of the STD I for initially-FF cars. Full-time all-wheel drive with a center differential (torque distribution between front and rear wheels - 30:70), locking by electronically controlled hydromechanical clutch.

Description - see review "Toyota AWD. i-Four".

"+" Full-time all-wheel drive, no need to control by driver.
"-" No full locking, complicated design (system is linked to ABS/VSC)

ModelProductionTransmissionDifferential locking
Aristo 1401992-1997A340H + UF1AEcenter - hydromechanical clutch
Brevis 102001-2007A340H + UF1AEcenter - hydromechanical clutch
Crown 1401992-1995A340H + UF1AEcenter - hydromechanical clutch
Crown 1501995-1999A340H,A341H + UF1AEcenter - hydromechanical clutch
Crown 1701999-2004A340H,A341H + UF1AEcenter - hydromechanical clutch
Crown 1802003-2008A750H,A760H,A761H + UF1AEcenter - hydromechanical clutch
Crown 2002008-2013A760H + UF1AEcenter - hydromechanical clutch
Crown GRS2112013-2018A760H + UF1AEcenter - hydromechanical clutch
Lexus IS 202005-2013A760H + UF1AEcenter - hydromechanical clutch
Lexus IS GSE352013-..A760H + UF1AEcenter - hydromechanical clutch
Lexus GS 1902005-2011A760H + UF1AEcenter - hydromechanical clutch
Lexus GS 102011-2020A760H + UF1AEcenter - hydromechanical clutch
Lexus RC GSC15.162014-..A760H + UF1AEcenter - hydromechanical clutch
Mark II 901993-1996A340H + UF1AEcenter - hydromechanical clutch
Mark II 1001996-2000A340H + UF1AEcenter - hydromechanical clutch, rear - LSD (opt.)
Mark II 1102000-2004A340H + UF1AEcenter - hydromechanical clutch, rear - LSD (opt.)
Mark II Blit 1102002-2007A340H + UF1AEcenter - hydromechanical clutch
Mark X 1202004-2009A750H + UF1AEcenter - hydromechanical clutch
Mark X 1302009-2019A760H + UF1AEcenter - hydromechanical clutch
Progres 101999-2007A340H + UF1AEcenter - hydromechanical clutch

2.1.4. Full-Time (Torsen)

Full-time four wheel drive, with an asymmetrical Torsen LSD type center differential
The development of the classic i-Four scheme stopped at the 6-speed automatic stage, while at more expensive and later models (including hybrids) used a simplified 4WD - with a mechanical Torsen-type differential (torque distribution between the front and rear axles - 40:60) and gear transmission in the transfer front drive section.

Detailed description - "Toyota AWD. Torsen".

ModelProductionTransmissionDifferential locking
Crown AWS211.2152014-2018L210F + LF1Acenter - LSD Torsen
Crown AZSH212018-2022L210F + LF1Acenter - LSD Torsen
Lexus IS AVE352015-..L210F + LF1Acenter - LSD Torsen
Lexus LS USF45.462006-2017AA80F + LF1Acenter - LSD Torsen
Lexus LS UVF45.462006-2017L110F + LF1Acenter - LSD Torsen
Lexus LS GVF552017-..L310F + LF1Acenter - LSD Torsen
Lexus LS VXFA552017-..AGA0F + LF1Acenter - LSD Torsen

2.1.5. Full-Time TL (Dual Range Diff Lock) type

Full-time four wheel drive, with a asymmetrical center differential, locking by Torsen LSD with the possibility of full locking, low range
Modern mid- and full-size SUVs are obtained with full-time all-wheel drive, asymmetrical Torsen differential, full locking mechanism, chain drive to the front wheels, low range. Torque distribution between the front and rear wheels - 40:60 (nominal) and 28:72 to 58:42 (dynamic, depending on driving conditions).






Low-grade version have single lever (LC 120) or the controller, providing three modes - H4F, H4L, L4L. Other versions have splitted control for center differential and low range gear, thar allows to use L4F mode.
H4↔L4 - when the vehicle is stationary and at "N" range of transmission.
Center differential lock - at speed below 100 km/h

ModelProductionTransmissionDifferential locking
4Runner 2852009-..5AT A750Fcenter - LSD Torsen + mechanical, rear - mechanical (opt.)
Fortuner 502005-20154/5AT A340F,A750F+VF4Bcenter - LSD Torsen + mechanical, rear - LSD/mechanical (opt.)
Land Cruiser Prado 1202002-20104/5AT A340F,A343F,A750F+VF4BMcenter - LSD Torsen + mechanical, rear - LSD/mechanical (opt.)
Land Cruiser Prado 1502009-..4/5/6AT A343F,A750F,AC60F+VF4BMcenter - LSD Torsen + mechanical, rear - mechanical (opt.)
Land Cruiser 2002007-20215/6AT A750F,AB60F+JF2Acenter - LSD Torsen + mechanical, rear - LSD/mechanical (opt.)
Land Cruiser 3002021-..10AT AJA0F, 6AT AC60F + JF2Acenter - LSD Torsen + mechanical, front - mech (opt.), rear - LSD/mech (opt.)
Lexus GX 1502009-..5/6AT A750F,A760F+VF4BMcenter - LSD Torsen + mechanical
Lexus LX 2002007-20216AT AB60F+JF2Acenter - LSD Torsen + mechanical
Lexus LX 3002021-..10AT AJA0F + JF2Acenter - LSD Torsen + mechanical, front - mech (opt.), rear - LSD/mech (opt.)

2.1.6. Full-Time (Daihatsu)


Full-time four wheel drive, with a symmetrical center differential and the possibility of full locking

This type appeared along with the re-branded Daihatsu models: symmetrical (50:50) bevel-gear center differential, full locking mechanism by vacuum servo, a chain drive to the front output shaft.

ModelProductionTransmissionDifferential locking
Rush J210E *2006-20164AT FR8center - mechanical, rear - LSD (opt.)
Townace/Liteace S41# *2008-..4AT FE8center - mechanical

2.1.7. Full-Time HD (Dual Range Diff Lock)

Full-time four wheel drive, with a symmetrical center differential and the possibility of full locking, low range

The first full-time in Land Cruiser family. A typical features of the heavy-duty transfer - gear drive, low range gear performed via countershaft (instead of a planetary), bevel type center differential.

ModelProductionTransmissionDifferential locking
Land Cruiser 80
(high grade)
1990-19984AT A343F + HF2ACD - mech, FD - mech (opt), RD - LSD/mech (opt)
Land Cruiser 1001998-20074AT A442F, 5AT A750F + HF2ACD - mech, FD - mech (opt), RD - LSD/mech (opt)

2.1.8. Full-Time HD (Dual Range Diff Lock + Visc)

Full-time four wheel drive, with a symmetrical center differential and the possibility of full locking, low range

A rare variant of the previous type, used during the introduction of ABS.


ModelProductionTransmissionDifferential locking
Land Cruiser 80
(high grade)
1990-19984AT A343F + HF2AVCD - mech, FD - mech (opt), RD - LSD/mech (opt)
Lexus LX4501995-19984AT A343F + HF2AVCD - mech, FD - mech (opt), RD - LSD/mech (opt)



2.2. Part-time all-wheel drive

2.2.1. Part-Time - Hub type

Basic rear-wheel drive, no center differential, front wheels are mechanically connected
One of the simplest types of all-wheel drive - with forced connection of front axle. Transfer have a reduction gear (planetary) for heavy-duty conditions, that operates in 4WD mode.

Transfer is controlled by lever, front drive shafts are connected to wheels with mechanical freewheel hubs (manual switching).

At the second variant used electric hubs and actuators at transfer.

"+" Relative simplicity, reduction gear availability.
"-" 4WD mode can be used on slippery surfaces only (rain, ice, snow). Otherwise, noise increasing, fuel consumption increasing, steering control deteriorates, and most importantly - highly worn tires and the transmission components. Mechanical hubs are quite reliable, but not easy-to-use, electrical - not so reliable.

Shift order:
2WD→4WD - at speed below 80 km/h with accelerator released, not engage during slipping (only after a full stop).
4WD→2WD - - at any speed.
4WD-H→4WD-L - when the vehicle is stationary and at "N" range of transmission.
4WD-L→4WD-H - when the vehicle is stationary and at "N" range of transmission.

ModelProductionTransmissionDifferential locking
4Runner 1851995-2000A340Frear - mechanical (opt.)
HiAce H10#..12#1989-1995A45DF,A340Frear - LSD (opt.)
LiteAce/TownAce 301992-1996A45DFrear - LSD (opt.)
Tacoma 160-1701995-2000A340Frear - mechanical (opt.)

2.2.2. Part-Time - ADD type

Basic rear-wheel drive, no center differential, front wheels are mechanically connected

In order to make front axle connection easy and get away from electric hubs, ADD (Automatic Disconnecting Differential) was implemented, which disconnect one of front axle shafts by actuator. As a result, rotation from wheels is not transmitted to the front propeller shaft, but the front axle gears are permanently lubricated.






4WD control - electric (by '4WD' button on the transfer lever) or semi-mechanical (by lever, similar to PT-Hub). Modern models have controller instead of the lever.


Shift order:
2WD→4WD - at speed below 80 km/h with accelerator released, not engage during slipping.
4WD→2WD - at any speed.
4WD-H↔4WD-L - when the vehicle is stationary, N range of transmission.

In the mid-2010s, a new type of transfer case appeared (equipped with an electromagnetic synchronizer), in the 2020s introduced a new compact electromagnetic actuator of ADD, located in the differential case directly.

Shift order:
H2↔H4 - at speed below 100 km/h.
H4↔L4 - when the vehicle is stationary, N range of transmission.

ModelProductionTransmissionDifferential locking
4Runner 1851995-2002A340Frear - mechanical (opt.)
FJ Cruiser2006-2018A750Frear - mechanical (opt.)
Fortuner 1502015-..AC60Frear - mechanical (opt.)
Hilux 202004-2015A340F,A343F,A750Frear - mechanical/LSD (opt.)
Hilux 1202015-..A750F,AC60Frear - mechanical (opt.)
HiLux Surf 1301989-1995-rear - LSD (opt.)
HiLux Surf 1851995-07.1998A340Frear - LSD (opt.)
HiLux N16#,17#1997-2004A343Frear - LSD (opt.)
Land Cruiser 90 (GX)1996-2002A343Frear - LSD (opt.)
Sequoia 802022-..AJA0F/L4A0F+WM1BMrear - mechanical
Tacoma 160-1701995-2004A340Frear - mechanical (opt.)
Tacoma 2002004-2015A340F,A750Frear - mechanical/LSD (opt.)
Tacoma 3002015-..AC60Frear - mechanical (opt.)
Tundra 401999-2006A340F,A750Frear - LSD (opt.)
Tundra 502006-2021A750F,AB60F-
Tundra 702021-..AJA0F/L4A0F+WM1BMrear - mechanical

2.2.3. Part-Time ADD (kei-car)


Basic rear-wheel drive, no center differential, the front wheels are mechanically connected.

Formally, Daihatsu's light commercial models can be attributed to PT-ADD type. The transfer shift and the right front axle disconnecting are performed by vacuum actuators.

All-wheel drive control - by the only button on the instrument panel.

Option - rear differential mechanical locking.

Some details - "AWD of Hijet models"



ModelProductionTransmissionDifferential locking
Pixis Truck S211U *2011-20143AT PM3rear - mechanical (opt.)
Pixis Truck S510U *2014-20214AT NC9rear - mechanical (opt.)
Pixis Van S331M *2011-20214AT ND9/NP9

2.2.4. Part-Time - HD

Basic rear-wheel drive, no center differential, the front axle is mechanically connected, low range.

Oddly enough, the first Toyota full-size SUV with automatic transmsission was built later than their first light car. But the same scheme is still used.

A typical feature of the heavy-duty transfer - gear drive, low range gear performed via countershaft (instead of a planetary gear).

ModelProductionTransmissionDifferential locking
Land Cruiser 601984-1990ATFD - mech (opt), RD - LSD/mech (opt)
Land Cruiser 80
(low grade)
1990-1998ATFD - mech (opt), RD - LSD/mech (opt)
Land Cruiser 701985-ATFD - mech (opt), RD - LSD/mech (opt)
Land Cruiser 100
(low grade)
1998-2007ATFD - mech (opt), RD - LSD/mech (opt)
Land Cruiser Prado 701990-1996AT-



2.3. On-demand all-wheel drive

2.3.1. Viscous type (kei-car)

Basic rear-wheel drive, no center differential, the front wheels are connected via viscous coupling.

The simplest type with a viscous coupling located inside the transfer case. Control functions and additional options are not provided.




ModelProductionTransmissionDifferential locking
Sparky S231E *2000-20034AT

2.3.2. MPT type (kei-car)


Basic rear-wheel drive, no center differential, the front wheels are connected via multi-plate hydromechanical coupling.

The new type appeared along with a CVT for rear-wheel drive platforms - the front wheels are connected via electronically controlled clutch.

All-wheel drive control - by the 3-position mode switch: 2WD (rear-wheel drive) / 4WD AUTO (automatic torque distribution) / 4WD LOCK (maximal clutch pressure).

Option - rear differential mechanical locking.



ModelProductionTransmissionDifferential locking
Pixis Truck S510U *2021-..CVTrear - mechanical (opt.)
Pixis Van S710M *2021-..CVT

* - Daihatsu models have been sold under Toyota brand
Abbreviations: TM - transmission (gearbox, CVT), TR - transfer, FD - front differential, RD - rear differential, CD - center differential, CDC - hydraulic clutch, VC - viscous coupling, EC - electromechanic coupling.



Toyota all-wheel drive. Review
· ATC/DTC · V-Flex · DTV · i-Four · Torsen · E-Four ·
· C.Diff Auto A241H / A540H · C.Diff Lock · C.Diff Visc · FT-Visc ·