1995 TOYOTA SUPRA clutch

A340E(Others) AUTOMATIC TRANSMISSIONCOMPONENT PARTS INSTALLATION -
AT-1 13
15. INSTALL ASSEMBLED DIRECT CLUTCH, FORWARD
CLUTCH AND FRONT PLANETARY RING GEAR INTO
CASE
(a) Coat the bearing and race with petroleum jelly and install
them onto the ring gear.
Bearing and race diameter
mm (in.)
InsideOutside
Bearing32.6 (1.283)47.7 (1.878)
Race30.6 (1.205)53.6 (2.110)
(b) Install the assembled direct clutch, forward clutch and
front planetary ring gear into the transmission case.
(c) Using vernier calipers, measure the distance between the
sun gear input drum and direct clutch drum, as shown in
the illustration.
Height:
5.3 - 7.3 mm (0.209 - 0.287 in.)
If the values are non-standard, check for an improper
installation.
(d) Coat the assembled bearing and race with petroleum jelly
and install it onto the forward clutch.
Assembled bearing and race diameter
mm (in.)
InsideOutside
Bearing and race33.7 (1.327)47.6 (1.874)

A340E(Others) AUTOMATIC TRANSMISSIONCOMPONENT PARTS INSTALLATION -
AT-1 17
If the piston stroke is less than the limit, parts may have
been assembled incorrectly, check and reassemble
again.
If the piston stroke is non- standard, select another
flange.
HINT: There are 7 different thicknesses for the flange.
Flange thickness
mm (in.)
No.ThicknessNo.Thickness
773.3 (0.130)813.8 (0.150)
783.5 (0.138)823.9 (0.154)
793.6 (0.142)834.0 (0.157)
803.7 (0.146)
22. INSTALL OVERDRIVE PLANETARY GEAR UNIT WITH
OVERDRIVE DIRECT CLUTCH AND ONE- WAY
CLUTCH
(a) Coat the race with petroleum jelly and install them onto
the overdrive support.
Race diameter
mm (in.)
InsideOutside
Race37.1 (1.461)59.0 (2.323)
(b) Install the overdrive planetary ring gear.
(c) Coat the bearing and race with petroleum jelly and install
them onto the planetary ring gear.
Bearing and race diameter
mm (in.)
InsideOutside
Bearing26.0 (1.024)46.8 (1.843)
Race24.2 (0.953)47.8 (1.882)

A340E(Others) AUTOMATIC TRANSMISSIONCOMPONENT PARTS INSTALLATION -
AT-1 18
(d) Coat the race with petroleum jelly and install it onto the
planetary gear.
Race diameter
mm (in.)
InsideOutside
Race27.1 (1.067)41.8 (1.646)
(e) Install the overdrive planetary gear with the overdrive di-
rect clutch and one-way clutch.
(f) Coat the assembled bearing and race with petroleum jelly
and install it onto the overdrive direct clutch.
Bearing and race diameter
mm (in.)
InsideOutside
Bearing and race28.9 (1.138)50.2 (1.976)
23. INSTALL OIL PUMP INTO CASE
(a) Coat the race with petroleum jelly and install it onto the oil
pump.
Race diameter
mm (in.)
InsideOutside
Race28.1 (1.106)47.3 (1.862)
(b) Coat a new O-ring with ATF and install it around the pump
body.
(c) Place the oil pump through the input shaft, and align the
bolt holes of the pump body with the transmission case.
(d) Hold the input shaft, and lightly press the oil pump body
to slide the oil seal rings into the O/D direct clutch drum.
NOTICE: Do not push on the oil pump strongly, or the oil
seal ring will stick to the direct clutch drum.

A340E(Others) AUTOMATIC TRANSMISSIONCOMPONENT PARTS INSTALLATION -
AT-1 19
(e) Install the 7 bolts.
Torque: 22 N´m (220 kgf´cm, 16 ft´lbf)
24. CHECK INPUT SHAFT ROTATION
Make sure the input shaft rotates smoothly.
25. INSTALL THROTTLE CABLE
(a) Coat a new O-ring with ATF and install it to the cable.
(b) Install the cable to the case.
26. INDIVIDUAL PISTON OPERATION INSPECTION
Check for the sound of operation while applying com-
pressed air into the oil hole indicated in the illustration.
HINT: When inspecting the O/D direct clutch, check with
the C
0 accumulator piston hole closed.
If there is no noise, disassemble and check the installa-
tion condition of the parts.
(1) O/D direct clutch
(2) Direct clutch
(3) Forward clutch
(4) O/D brake
(5) Second coast brake
(6) Second brake
(7) First and reverse brake

 COMPONENT FUNCTION
 O/D Direct Clutch (C0) Connects overdrive sun gear and overdrive carrier
 
 O/D Brake (B0) 
 Prevents overdrive sun gear from turning either clockwise or counterclockwise
 
 
O/D One±Way Clutch (F0) 
 
When transmission is being driven by engine, connects overdrive sun gear and
overdrive carrier
 Forward Clutch (C1) Connects input shaft and front planetary ring gear
 Direct Clutch (C2) Connects input shaft and front & rear planetary sun gear
 
 2nd Coast Brake (B1)
 
 Prevents front & rear planetary sun gear from turning either clockwise or coun-
terclockwise
 
 
 
2nd Brake (B2)
 
 
 
Prevents outer race of F1 from turning either clockwise or counterclockwise,
thus preventing front & rear planetary sun gear from turning counterclockwise
 
 
1st & Reverse Brake (B3) 
 
Prevents rear planetary carrier from turning either clockwise or counterclock-
wise
 
 No. 1 One±Way Clutch (F1) 
 
When B2 is operating, prevents front & rear planetary sun gear from turning
counterclockwise
 No. 2 One±Way Clutch (F2) Prevents rear planetary carrier from turning coiunterclockwise
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONOPERATIONAT1±3

HYDRAULIC CONTROL SYSTEM
The hydraulic control system is composed of the oil pump, the valve body, the solenoid valves and the
clutches and brakes, as well as the fluid passages which connect all of these components. Based on the
hydraulic pressure created by the oil pump, the hydraulic control system governs the hydraulic pressure
acting on the torque converter clutch, clutches and brakes in accordance with the vehicle driving condi-
tions.
There are three solenoid valves on the valve body. These solenoid valves are turned on and off by signals
from the ECM to operate the shift valves. These shift valves then switch the fluid passages so that fluid
goes to the torque converter clutch and planetary gear units.
Except for the solenoid valves, the hydraulic control system of the electronically controlled transmission
is basically the same as that of the fully hydraulic controlled automatic transmission.
HYDRAULIC CONTROL SYSTEM
VALVE BODY
OIL PUMP
ECMSOLENOID VALVES
CLUTCHES & BRAKES
Hydr. pressure control
Fluid passage switchingPlanetary gear sets
Torque Converter Clutch
w LINE PRESSURE
Line pressure is the most basic and important pressure used in the automatic transmission, because it is
used to operate all of the clutches and brakes in the transmission.
If the primary regulator valve does not operate correctly, line pressure will be either too high or too low. Line
pressure that is too high will lead to shifting shock and consequent engine power loss due to the greater
output required from the oil pump; line pressure that is too low will cause slippage of clutches and brakes,
which will, in extreme cases, prevent the vehicle from moving. Therefore, if either of these problems are
noted, the line pressure should be measured to see if it is within standard.
w THROTTLE PRESSURE
Throttle pressure is always kept in accordance with the opening angle of the engine throttle valve. This
throttle pressure acts on the primary regulator valve and, accordingly, line pressure is regulated in re-
sponse to the throttle valve opening.
In the fully hydraulic controlled automatic transmission, throttle pressure is used for regulating line pressure
and as signal pressure for up±shift and down±shift of the transmission. In the electronically controlled
transmission, however, throttle pressure is used only for regulating line pressure. Consequently, improper
adjustment of the transmission throttle cable may result in a line pressure that is too high or too low. This,
in turn, will lead to shifting shock or clutch and brake slippage. AT1±6
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONOPERATION

ELECTRONIC CONTROL SYSTEM
The electronic control system, which controls the shift points and the operation of the lock±up clutch, is
composed of the following three parts:
1. Sensors
These sensors sense the vehicle speed, throttle opening and other conditions and send this data to the
ECM in the form of electrical signals.
2. ECM
The ECM determines the shift and lock±up timing based upon the signals from sensors, and controls the
solenoid valves of the hydraulic control unit accordingly.
3. Actuators
These are three solenoid valves that control hydraulic pressure acting on the hydraulic valves to control
shifting and lock±up timing.
SENSORSECM
DRIVING PATTERN
SELECTOR
PARK/NEUTRAL
POSITIOIN SWITCH
THROTTLE POSITIOIN
SENSOR
VEHICLE SPEED
SENSOR
STOP LIGHT SWITCH
O/D MAIN SWITCH
CRUISE CONTROL
ECU
ENGINE COOLANT TEM-
PERATURE SENSOR
A/T FLUID
TEMPERATURE SENSOR
Back±up system
Self±diagnostic
system
Control of lock±
up timing
Control of shift
timing
ACTUATORS
NO. 1
SOLENOID VALVE
NO. 2
SOLENOID VALVE
LOCK±UP
SOLENOID VALVE
O/D OFF INDICA-
TOR LIGHT
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONOPERATIONAT1±7

FUNCTION OF ECU
w Control of Shifting Timing
The ECM has programmed into its memory the optimum shift pattern for each shift lever position (D, 2, L
position) and driving mode (Normal or Manual).
Based on the appropriate shift pattern, the ECM turns No.1 and No.2 solenoid valves on or off in accor-
dance with the vehicle speed signal from the vehicle speed sensor and the throttle opening signal from the
throttle position sensor. In this manner, the ECM operates each shift valve, opening or closing the fluid pas-
sages to the clutches and brakes to permit up±shift or down±shift of the transmission.
HINT: The electronic control system provides shift timing and lock±up control only while the vehicle is travel-
ing forward. In REVERSE, PARK, and NEUTRAL, the transmission is mechanically, not electronically con-
trolled.
w Control of Overdrive
Driving in overdrive is possible if the O/D main switch is on and the shift lever is in the D position. However,
when the vehicle is being driven using the cruise control system (CCS), if the actual vehicle speed drops
to about 4 km/h (2 mph) below the set speed while the vehicle is running in overdrive, the CCS ECU sends
a signal to the ECM to release the overdrive and prevent the transmission from shifting back into overdrive
until the actual vehicle speed reaches the speed set in the CCS memory.
On this model, if the engine coolant temperature falls below 60°C (140°F), the ECM sends a signal to the
ECM, preventing the transmission from up±shifting into overdrive.
w Control of Lock±Up System
The ECM has programmed in its memory a lock±up clutch operation pattern for each driving mode (Normal
of Manual). Based on this lock±up pattern, the ECM turns lock±up solenoid valve on or off in accordance
with the vehicle speed signals received from the vehicle speed sensor and the throttle opening signals from
the throttle position sensor.
Depending on whether lock±up solenoid valve is on or off, the lock±up relay valve performs changeover
of the fluid passages for the converter pressure acting on the torque converter clutch to engage or disen-
gage the lock±up clutch.
Mandatory Cancellation of Lock±Up System:
If any of the following conditions exist, the ECM turns off lock±up solenoid valve to disengage the lock±up
clutch.
1) The brake light switch comes on (during braking).
2) The IDL points of the throttle position sensor close (throttle valve fully closed).
3) The vehicle speed drops 4 km/h (2 mph) or more below the set speed while the cruise control system
is operating.
4) The engine coolant temperature falls below 60°C (140°F) and vehicle speed is under 60 km/h (37
mph), or 35°C (95°F) and vehicle speed is under 40 km/h (25 mph).
The purpose of 1) and 2) above is to prevent the engine from stalling if the rear wheels lock up.
The purpose of 3) is to cause the torque converter clutch to operate to obtain torque multiplication. The
purpose of 4) is both to improve general driveability, and to speed up transmission warm±up.
Also, while the lock±up system is in operation, the ECM will temporarily turn it off during up±shift or down±
shift in order to decrease shifting shock. AT1±8
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONOPERATION