2007 TOYOTA SIENNA automatic transmission

SS–28SERVICE SPECIFICATIONS – U151E AUTOMATIC TRANSAXLE
SS
Flange thickness Mark
1 1.8 mm (0.071 in.)
2 1.9 mm (0.075 in.)
3 2.0 mm (0.079 in.)
4 2.1 mm (0.083 in.)
5 2.2 mm (0.087 in.)
6 2.3 mm (0.091 in.)
7 2.4 mm (0.094 in.)
8 2.5 mm (0.098 in.)
U/D planetary gear
Preload (at 60 rpm) 0.50 to 1.42 N*m (5.1 to 14.5 kgf*cm, 0.06 to 0.17 in.*lbf)
Front planetary gear
Turning torque (at 60 rpm) New
Bearing0.51 to 1.02 N*m (5.1 to 10.0 kgf*cm, 4.4 to 8.7 in.*lbf)
Used
Bearing0.26 to 0.51 N*m (2.7 to 5.2 kgf*cm, 2.3 to 4.5 in.*lbf)
Input shaft
End play0.262 to 1.249 mm (0.0103 to 0.0492 in.)
Transaxle rear cover
Bearing press fit depth 20.55 to 21.25 mm (0.8091 to 0.8366 in.)
Transmission valve body
Valve body installation bolt length A 41 mm (1.614 in.)
B 57 mm (2.244 in.)
C 25 mm (0.984 in.)
Accumulator
Spring Free length/Outer diameter Color
B
3Inner 62.00 (2.4409) / 15.50 (0.610) Purple
Outer 74.23 (2.9224) / 16.50 (0.649) Purple
C
260.96 (2.3999) / 14.10 (0.555) Yellow
C
372.20 (2.8425) / 19.0 (0.748) Colorless
Front differential (U151E)
Backlash0.05 to 0.20 mm (0.0020 to 0.0079 in.)
Thrust washer thickness Mark
- 1.625 mm (0.0640 in.)
- 1.725 mm (0.0679 in.)
- 1.825 mm (0.0719 in.)
Preload (at 60 rpm) New
bearing0.20 to 0.69 N*m (2.0 to 7.0 kgf*cm, 1.8 to 6.1 in.*lbf)
Used
bearing0.10 to 0.35 N*m (1.0 to 3.6 kgf*cm, 0.9 to 3.1 in.*lbf) 1st & reverse brake

SS–34SERVICE SPECIFICATIONS – U151F AUTOMATIC TRANSAXLE
SS
Flange thickness Mark
1 3.0 mm (0.118 in.)
2 3.2 mm (0.126 in.)
3 3.4 mm (0.134 in.)
1st & reverse brake
Pack clearance1.16 to 1.35 mm (0.0457 to 0.0531in.)
Return spring free length15.53 mm (0.6114 in.)
Flange thickness Mark
1 1.8 mm (0.071 in.)
2 1.9 mm (0.075 in.)
3 2.0 mm (0.079 in.)
4 2.1 mm (0.083 in.)
5 2.2 mm (0.087 in.)
6 2.3 mm (0.091 in.)
7 2.4 mm (0.094 in.)
8 2.5 mm (0.098 in.)
U/D planetary gear
Preload (at 60 rpm) 0.50 to 1.42 N*m (5.1 to 14.5 kgf*cm, 0.06 to 0.17 in.*lbf)
Front planetary gear
Turning torque (at 60 rpm) New
Bearing0.51 to 1.02 N*m (5.1 to 10.0 kgf*cm, 4.4 to 8.7 in.*lbf)
Used
Bearing0.26 to 0.51 N*m (2.7 to 5.2 kgf*cm, 2.3 to 4.5 in.*lbf)
Input shaft
End play0.262 to 1.249 mm (0.0103 to 0.0492 in.)
Transaxle rear cover
Bearing press fit depth 20.55 to 21.25 mm (0.8091 to 0.8366 in.)
Transmission valve body
Valve body installation bolt length A 41 mm (1.614 in.)
B 57 mm (2.244 in.)
C 25 mm (0.984 in.)
Accumulator
Spring Free length/Outer diameter Color
B
3Inner 62.00 (2.4409) / 15.50 (0.610) Purple
Outer 74.23 (2.9224) / 16.50 (0.649) Purple
C
260.96 (2.3999) / 14.10 (0.555) Yellow
C
372.20 (2.8425) / 19.0 (0.748) Colorless
Front differential (U151F)
Side gear backlash 0.05 to 0.20 mm (0.0020 to 0.0079 in.) U/D brake

AX–6U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
SYSTEM DESCRIPTION
1. SYSTEM DESCRIPTION
(a) The ECT (Electronic controlled automatic
transmission/transaxle) is an automatic
transmission/transaxle that electronically controls
shift timing using the ECM. The ECM detects
electrical signals that indicate engine and driving
conditions, and controls the shift point, based on
driver habits and road conditions. As a result, fuel
efficiency and power transmission performance are
improved.
Shift shock has been reduced by controlling the
engine and transmission simultaneously.
In addition, the ECT has features such as follows:
• Diagnostic function.
• Fail-safe function when a malfunction occurs.

U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–13
AX
MECHANICAL SYSTEM TESTS
1. PERFORM MECHANICAL SYSTEM TESTS
(a) Measure the stall speed.
The object of this test is to check the overall
performance of the transaxle and engine by
measuring the stall speeds in the D position.
NOTICE:
• Driving test should be done on a paved road
(a nonskid road).
• Perform the test at the normal operating ATF
(Automatic Transmission Fluid) temperature
50 to 80
C (122 to 176F).
• Do not continuously run this test for longer
than 10 seconds.
• To ensure safety, do this test in a wide, clear
level area which provides good traction.
• The stall test should always be carried out in
pairs. One technician should observe the
conditions of wheels or wheel stoppers
outside the vehicle while the other is doing
the test.
(1) Chock the 4 wheels.
(2) Connect the intelligent tester together with the
CAN VIM (controller area network vehicle
interface module) to the DLC3.
(3) Fully apply the parking brake.
(4) Keep your left foot pressed firmly on the brake
pedal.
(5) Start the engine.
(6) Shift into the D position. Press all the way down
on the accelerator pedal with your right foot.
(7) Quickly read the stall speed at this time.
Stall speed:
2,300 +- 150 rpm
Evaluation:
Problem Possible cause
(a) Stall engine speed is low in D position• Engine power output may be insufficient
• Stator one-way clutch not operating properly
HINT:
If the value is less than the specified value by 600 rpm or more, the
torque converter could be faulty.
(b) Stall engine speed is high in D position• Line pressure is too low
• Forward clutch slipping
• U/D (Underdrive) brake slipping
• U/D (Underdrive) one-way clutch is not operating properly
• No.1 one-way clutch not operating properly
• Improper fluid level

AX–14U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
(b) Measure the time lag.
(1) When the shift lever is shifted while the engine is
idling, there will be a certain time lapse or lag
before the shock can be felt. This is used for
checking the condition of the clutch and brake.
NOTICE:
• Perform the test at the normal operating
ATF (Automatic Transmission Fluid)
temperature: 50 to 80
C (122 to 176F).
• Be sure to allow 1 minute interval between
tests.
• Perform the test three times, and measure
the time lags. Calculate the average value
of the three time lags.
• When conducting stall test, do not
continue more than 10 seconds.
(2) Connect the intelligent tester together with the
CAN VIM (controller area network vehicle
interface module) to the DLC3.
(3) Fully apply the parking brake.
(4) Start and warm up the engine and check idle
speed.
Idle speed:
approx. 700 rpm (In N position and A/C
OFF)
(5) Shift the lever from N to D position. Using a stop
watch, measure the time from when the lever is
shifted until the shock is felt.
Time lag:
N
D less than 1.2 seconds
(6) In the same way, measure the time lag for N

R.
Time lag:
N
R less than 1.5 seconds
Evaluation (If N
D or N R time lag is longer than the specified):
Problem Possible cause
N
D time lag is longer• Line pressure is too low
• Forward clutch worn
• No.1 one-way clutch is not operating properly
• U/D (Underdrive) one-way clutch is not operating
• U/D (Underdrive) brake worn
N
R time lag is longer• Line pressure is too low
• Reverse clutch worn
• 1st and reverse brake worn
• U/D (Underdrive) brake worn

U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–15
AX
HYDRAULIC TEST
1. PERFORM HYDRAULIC TEST
(a) Measure the line pressure.
NOTICE:
• Perform the test at the normal operating ATF
(Automatic Transmission Fluid) temperature:
50 to 80
C (122 to 176F).
• The line pressure test should always be
carried out in pairs. One technician should
observe the conditions of wheels or wheel
stoppers outside the vehicle while the other
is performing the test.
• Be careful to prevent SST hose from
interfering with the exhaust pipe.
• This Check must be conducted after checking
and adjusting engine.
• Perform under condition that A/C is OFF.
• When conducting stall test, do not continue
more than 10 seconds.
(1) Warm up the ATF (Automatic Transmission
Fluid).
(2) Lift the vehicle up.
(3) Remove the engine under cover.
(4) Connect the intelligent tester together with the
CAN VIM (controller area network vehicle
interface module) to the DLC3.
(5) Remove the test plug A on the transaxle case
front left side and install the SST.
SST 09992-00095 (09992-00231, 09992-
00271)
NOTICE:
There is a difference in installation point
between D position and R position.
(6) Start the engine.
(7) Using intelligent tester, shift to D position and
hold 3rd gear by active test, and measure the
line pressure in idling.
Specified line pressure:
(8) Turn the ignition switch off.
C160153E01
Condition
D position kPa (kgf / cm2, psi)
Idling372 to 412 kPa
(3.8 to 4.2 kgf/cm
2, 54 to 60 psi)

AX–16U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
(9) Disconnect the connector of the transmission
wire.
HINT:
Disconnect the connector only when performing
the D position stall test.
(10)Start the engine.
(11)Firmly depress the brake pedal, shift to the D
position, depress the accelerator pedal all the
way down and check the line pressure while the
stall test is performed.
Specified line pressure:
(12)Turn the ignition switch off.
(13)Remove the SST, install the test plug A.
(14)Remove the test plug B, install the SST and
start engine.
SST 09992-00095 (09992-00231, 09992-
00271)
(15)Connect the transmission wire connector,
depress the brake pedal firmly, shift to the R
position and check that the line pressure while
the engine is idling and during the stall test.
Specified line pressure:
(16)Remove the SST, install the test plug B.
(17)Clear the DTC.
Evaluation:
C160154E01
Condition
D position kPa (kgf / cm2, psi)
Stall test931 to 1,031 kPa
(9.5 to 10.5 kgf/cm
2, 135 to 150 psi)
Condition
R position kPa (kgf / cm
2, psi)
Idling672 to 742 kPa
(6.9 to 7.6 kgf/cm
2, 97 to 108 psi)
Stall test1,768 to 1,968 kPa
(18.0 to 20.1 kgf/cm
2, 256 to 285 psi)
Problem Possible cause
Measured values are higher than specified in all positions• Shift solenoid valve SLT defective
• Regulator valve defective
Measured values are lower than specified in all positions• Shift solenoid valve SLT defective
• Regulator valve defective
• Oil pump defective
• U/D (Underdrive) direct clutch defective
Pressure is low in the D position only• D position circuit fluid leak
• Forward clutch defective
Pressure is low in the R position only• R position circuit fluid leak
• Reverse clutch defective
• 1st and reverse brake defective

U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–17
AX
MANUAL SHIFTING TEST
1. PERFORM MANUAL SHIFTING TEST
HINT:
• With this test, it can be determined whether the
trouble occurs in the electrical circuit or is a
mechanical problem in the transaxle.
• If any abnormalities are found in the following test, the
problem is in the transaxle itself.
(a) Disconnect the connector of the transmission wire.
(b) Drive with the transmission wire disconnected.
Shifting the shift lever in the order of L, 2, 3, 4 and D
position to check whether the shifting condition
changes the table below.
HINT:
When driving with the transmission wire
disconnected, the shift lever position is in L or 2, the
gear position is held in 3rd and the shift lever
position is in 3, 4 or D, the gear position is held in
4th. However, when the shift position is in R or P, the
operation is same as usual.
(c) Connect the connector of the transmission wire.
(d) Clear the DTC (See page AX-27).
C160154E01
Shift Position Shifting Condition
L
2 No Shift (Not Change)
2
3 Down Shift Up Shift
3
4 D No Shift (Not Change)