2004 ISUZU TF SERIES reverse

7A4–132 UNIT REPAIR (AW30–40LE)
Special Tools
ILLUSTRATIONTOOL NO.
TOOL NAME
J–37227
Holding fixture
J–3289–20
Holding fixture base
J–37228
Oil pan seal cutter
J–23327–1
Spring compressor
J–9617
Oil seal installer; oil
pump
J–37233
Spring compressor; OD
brake piston
J–29770–A
Oil pressure gauge
J–25048
Spring compressor
J–37236
Reaction sleeve puller;
first and reverse brake
J–37237
Piston puller; first and
reverse brake
J–37232–2
Oil seal installer;
manual valve shaft seal
installer & remover
J–35467
Onennway clutch
testing tool; torque
converter ILLUSTRATIONTOOL NO.
TOOL NAME

CONSTRUCTION AND FUNCTION 7A1-3

DESCRIPTION
CONSTRUCTION



































1 Converter Housing 6 Low Clutch 11 Oil Pump
2 Torque Converter 7 Low & Reverse Brake 12 Control Valve
3 High Clutch 8 Output Shaft 13 Low One-way Clutch
4 Reverse Clutch 9 Extension Housing 14 Parking Gear
5 2-4 Brake 10 Input Shaft

Figure 1. Construction of Automatic Transmission

The JR405E automatic transmission is electrically controlled by a microcomputer transmission control module
(TCM). There are four forward speeds and one reverse speed.
This JR405E automatic transmission employs a clutch pressure direct control system (Direct Electronic Shift
Control: DESC) using a duty cycle type solenoid, which ensures high shift quality.
This transmission also controls learning and constantly checks the time of each clutch and brake required for
the speed change to match this time with the target value for the optimum speed change.

The TCM will automatically select the most appropriate shift points and lock-up points depending on the
throttle opening angle, the vehicle speed and the vehicle load.
If any trouble arises in the vehicle sensor, throttle sensor, solenoid, etc., the fail-safe control function is
activated to keep the running performance.
Problems with the sensors, the solenoids can be quickly detected with the self diagnosis procedure described
in this manual.

The JR405E automatic transmission consists of the torque converter, the oil pump, the input shaft, the out put
shaft, the planetary gears and the control valve.
The gear train consists of two planetary gear sets and three multiple plate clutches in combination with two
multiple plate brakes and a one-way clutch.
2WD
4WD

7A1-4 CONSTRUCTION AND FUNCTION
MAIN DATA AND SPECIFICATION
Model JR405E
Torque Converter Type Three Elements, One Stage & Two Phase Type
With Lock-up Function
Torque Converter Stall Torque Ratio 1.8
Name ATF DEXRON

Quantity 9.2L-9.6L AT F
Cooling System Water Cooled Type (Radiator)
1st 2.786
2nd 1.546
3rd 1.000
4th (Over Drive) 0.694
Gear Ratio
Reverse 2.273
Low Clutch L/C 7
High Clutch H/C 5
Reverse Clutch R/C 2Number of Disc Clutch
Low One-way Clutch L/O.C 1 Set
Low & Reverse
Brake L&R/B 6
Brake
2-4 Brake 2-4/B 5Number of Disc
Sun Gear 33
Pinion
Gear 21Front Planetary
Ring Gear 75
Sun Gear 42
Pinion
Gear 17
Planetary Gear Unit
Rear Planetary
Ring Gear 75Number of Teeth

7A1-6 CONSTRUCTION AND FUNCTION
ELECTRONIC CONTROL COMPONENTS LOCATION

4WD Only 4WD Only
Instrument panel (Meter)







Speed meter (2WD Only)
Shift position indicator lamp
POWER DRIVE, 3rd START
indicator lamp
A/T OIL TEMP indicator lamp
CHECK TRANS indicator lam
p

Brake pedal





Brake Switch
Select lever








Power Drive
, 3rd Start select switch
Transmission Control Module (TCM)
Electrical source






Ignition
Battery voltage
Speed sensor
Turbine sensor
Inhibitor switch
ATF thermo sensor
High clutch oil pressure switch
2-4 brake oil pressure switch
Low & Reverse brake oil pressure
switch
Line pressure solenoid
Low clutch solenoid
High clutch solenoid
2-4 brake solenoid
Low & Reverse brake solenoid
Lock-up solenoid
Transmission
Transfer Control Module
Transfer




4L mode switch
Engine




Engine speed sensor
Throttle Position Sensor


Engine Control Module (ECM)
Data link connector

7A1-10 CONSTRUCTION AND FUNCTION
INPUT SHAFT

The input shaft has some oil holes, through which lubricating ATF is supplied to the torque converter,
bearings, etc.

The input shaft is fitted the turbine runner in the torque converter, reverse & high clutch drum and rear sun
gear by means of the spline. Therefore, the engine driving force received by the torque converter is
transmitted to the reverse & high clutch drum and rear sun gear.

OUTPUT SHAFT

The output shaft has some oil holes, through which the lubricating ATF is supplied to the bearings,
planetary gear unit, etc.

The output shaft transmits the engine driving force from the planetary gear to the propeller shaft.

The front internal gear is fitted with the rear carrier assembly by spline. The parking gear is also fitted by
spline. By fixing this gear mechanically, the output shaft is fixed as required when parking the vehicle.

GEAR SHIFTING MECHANISM

The JR405E consists of two sets of planetary gears, three multiple plate clutches, two multiple plate
brakes and a one-way clutch. They are activated in different combinations in any of four forward and one
reverse gear positions.

Principle of gear shifting (Figure 12)

Planetary gears have the advantage of a compact configuration because of the way they are constructed
with a single central shaft.

Also, unlike the manual transmission gears that require changing of gear mesh, the gear ratio of the
planetary gears can be changed more easily by locking, releasing or rotating only some of their parts.

A planetary gear is made up of a sun gear (1) at its center and pinion gears (2) each of which rotates
about its own center and also along the sun gear, as shown. They are all called in the internal gear (3).

Also, since the pinion gears are further supported by the planetary carrier (4), they rotate as a unit in the
same direction and at the same rate.

As shown above, each planetary gears are constructed of three elements; a sun gear, pinion gears, and
internal gear and a planetary carrier. Gear shifting is achieved by conditioning two of the three elements
namely the sun gear, internal gear and the planetary carrier.

The planetary gears are locked by the clutch, brake and one-way clutch according to the gear shifting.
















1. Sun Gear
2. Pinion Gear
3. Internal Gear
4. Planetary Carrier

Figure 12. Planetary Gear

CONSTRUCTION AND FUNCTION 7A1-11


The JR405E consists of two sets of planetary gears, which are called front planetary gear and rear
planetary gear.

The sun gear of front planetary gear is fixed to the drive plates of 2-4 brake and reverse clutch.

The planetary carrier of front planetary gear is fixed to the drum of low clutch, the drive plates of low &
reverse brake and the hub of high clutch.

The internal gear of front planetary gear and the planetary carrier of rear planetary gear are connected as
one, and they are fixed to output shaft.

The sun gear of rear planetary gear is fixed to input shaft.

The internal gear of rear planetary gear is fixed to the hub of low clutch.

Clutch and Brake

Basic structure of the clutch and brake is shown in the figures below.

In the figure A, the clutch plates (drive plate and driven plate) are in the fluid so that they slip against each
other transmitting no power.

Figure B shows the condition where the oil pressure is acting on the piston. The clutch plates are fitted
to each other under pressure transmitting the rotations of the clutch drum to the clutch hub.

When the oil pressure is removed from the piston, the clutch returns to the condition in the figure A by the
return spring.


Figure 13. Basic Construction of Clutch and Brake

Low Clutch, High Clutch and Reverse Clutch (Multi-Plate Clutch)

The multi-plate clutch is composed of drive plates and driven plates. By applying the oil pressure onto
the end surface of the plates, the clutch is engaged or disengaged. The oil pressure is adjusted with the
control valve according to the signal from the TCM.

All clutches use dish plates to prevent uncontrolled operation of the clutches when engaged, causing a
shock.

For the reverse clutch, a piston check ball is used to release the oil pressure for the purpose of preventing
the clutch drag due to oil pressure generated by residual ATF because of the centrifugal force while the
clutch is racing (under no oil pressure).

For the low clutch and high clutch, a centrifugal balance chamber always full of ATF is provided to offset
the excessive oil pressure, for the purpose of preventing the clutch drag due to oil pressure generated by
residual ATF because of the centrifugal force while the clutch is racing (under no oil pressure).

The solenoid in the control valve is driven based on the speed change signal from TCM and moves the
shift valve, thereby engaging the drive plate and driven plate through the piston of each clutch.

Resultantly, elements of the planetary gear unit are combined.

When the oil pressure is removed, the piston returns to the original position by the force of the return
spring.

7A1-12 CONSTRUCTION AND FUNCTION



Figure 14. Basic Construction of Low Clutch
and High Clutch Figure 15. Basic Construction of Reverse Clutch

Figure 16. Construction of Low Clutch Figure 17. Construction of High Clutch

Figure 18. Construction of Reverse Clutch

CONSTRUCTION AND FUNCTION 7A1-13

2-4 Brake and Low & Reverse Brake (Multi-Plate Brake)

The multi-plate brake is composed of drive plates and driven plates. By applying the oil pressure onto
the end surface of the plates, the clutch is engaged or disengaged. The oil pressure is adjusted with the
control valve according to the signal from the TCM.

All brakes use dish plates to prevent uncontrolled operation of the clutches when engaged, causing a
shock.

The solenoid in the control valve is driven based on the speed change signal from TCM and moves the
shift valve, thereby engaging the drive plate and driven plate through the piston of each clutch.

Resultantly, rotation of each element of the planetary gear unit is fixed.

When the oil pressure is removed, the piston returns to the original position by the force of the return
spring.




Figure 19. Construction of 2-4 Brake
Figure 20. Construction of Low & Reverse Brake

Low One-way Clutch

The low one-way clutch employs the sprag which locks the counterclockwise rotation of the front planetary
carrier and rear internal gear.

The one-way clutch outer race is fitted with the low clutch drum and the inner race with the transmission
case.

The outer race rotates freely clockwise but, when it attempts to rotate counterclockwise, the sprag
functions to lock the outer race.

When the vehicle is traveling in 1st gear in the D, 3 or 2range, the low one-way clutch locks the rear
internal gear via the low clutch. It is left free in the 2nd, 3rd or 4th gear position.


Figure 21. Construction of Low One-way Clutch