1987 MAZDA 626 differential

7C
AUTOMATIC TRANSAXLE
(3-Speed)
OUTLINE 7C— 2
SPECIFICATIONS 7C— 2
CROSS-SECTIONAL VIEW 7C— 3
OPERATION OF COMPONENTS . 7C— 4
FLUID PASSAGE LOCATION 7C— 5
TROUBLESHOOTING 7C— 8
GENERAL NOTE 7C— 8
QUICK DIAGNOSIS CHART 7C— 9
STEP 1
(PRELIMINARY INSPECTION).... 7C— 12
STEP 2 (STALL TEST) 7C— 14
STEP 3 (TIME LAG TEST) 7C— 17
STEP 4 (ROAD TEST) 7C— 18
STEP 5 (OIL PRESSURE TEST)... 7C— 20
ELECTRIC COMPONENTS 7C— 23
INHIBITOR SWITCH 7C— 23
KICK-DOWN SWITCH 7C— 23
KICK-DOWN SOLENOID 7C— 24
ON-VEHICLE MAINTENANCE 7C- 25
AUTOMATIC TRANSAXLE FLUID
(ATF) 7C— 25
SELECTOR LEVER 7C— 26
VACUUM DIAPHRAGM 7C— 27
REPLACEMENT OF CONTROL
VALVE 7C— 28
REPLACEMENT OF SERVO
PISTON RETURN SPRING 7C— 29
REMOVAL 7C— 30
PREPARATION 7C— 30
DISASSEMBLY 7C— 35
DISASSEMBLY-STEP 1 7C— 35
DISASSEMBLY-STEP 2 7C— 41
DISASSEMBLY-STEP 3 7C— 45
DISASSEMBLY-STEP 4 7C— 51
INSPECTION AND REPAIR 7C- 54
PRECAUTION 7C— 54
TORQUE CONVERTER 7C— 54
OIL PUMP 7C— 55
FRONT CLUTCH 7C— 58
REAR CLUTCH 7C— 62
REAR CLUTCH HUB 7C— 65
DRUM HUB 7C— 66
ONE-WAY CLUTCH INNER RACE 7C— 68
BAND SERVO 7C— 69
BRAKE BAND 7C— 70
PLANETARY CARRIER (FRONT).. 7C— 71
ONE-WAY CLUTCH 7C— 71
LOW AND REVERSE BRAKE 7C— 71
GOVERNOR 7C— 72
CONTROL VALVE BODY 7C— 75
DIFFERENTIAL 7C— 79
OUTPUT GEAR 7C— 82
IDLE GEAR 7C— 83
BEARING COVER ASSEMBLY .... 7C— 86
BEARING HOUSING 7C— 87
SIDE BEARING HOUSING 7C— 88
ASSEMBLY 7C— 89
PRECAUTION 7C— 89
ASSEMBLY-STEP 1 7C— 89
ASSEMBLY-STEP 2 7C— 98
ASSEMBLY-STEP 3 7C—106
ASSEMBLY-STEP 4 7C—111
INSTALLATION 7C—119
TORQUE SPECIFICATIONS 7C—119
HYDRAULIC CIRCUIT 7C—125
OUTLINE 7C—125
P RANGE 7C—126
R RANGE 7C—127
N RANGE 7C—128
D RANGE (1ST GEAR) 7C—129
D RANGE (2ND GEAR) 7C—130
D RANGE (3RD GEAR) 7C—131
D RANGE (KICK-DOWN; SHIFT
VALVES IN 2ND POSITION) 7C—132
2 RANGE (2ND GEAR) 7C—133
1 RANGE (1ST GEAR) 7C—134
1 RANGE (2ND GEAR) 7C—135
76G07C-001

OUTLINE 7C
CROSS-SECTIONAL VIEW
76G07C-003
1. Transaxle case
2. Front clutch
3. Rear clutch
4. Connecting shell
5. Rear clutch hub
6. Planetary carrier (front)
7. Sun gear
8. Low and reverse brake
9. One-way clutch
10. One-way clutch inner race
11. Planetary carrier (rear)
12. Drum hub assembly
13. Bearing housing
14. Output gear
15. Turbine shaft
16. Oil pump shaft
17. Bearing cover
18. Oil seal
19. Torque converter
20. Converter housing
21. Oil seal
22. Speedometer drive gear
63U07B-003
23. Side gear
24. Pinion gear
25. Pinion shaft
26. Differential gear case
27. Ring gear
28. Oil seal
29. Side bearing housing
30. Control valve body
31. Oil pan
32. Oil pump
7C-3

TROUBLESHOOTING
7C

ON VEHICLE -OFF VEHICLE
-

\ Inspection point
\
and
reference
\ page
Condition


in cd
ra
CM CM CM
I
I I
o
o o
I—
r~—
r—
7C—27
7C—23,24
Section
4A

7C—14
7C—20,22
7C-75

CM
0>
[—
CO
LO I
I I
O
O O
r^ r—
Section

5
CD CM
O
in (D
s
I
I I
o
o o
r—
r^

w
CM
r-
m f-
I
I I
o
o o
r-— I—
r-—
7C—54
7C-71
7C—66,

98

7C-68,

71 \ Inspection point
\
and
reference
\ page
Condition

ATR

level
and
condition

Selector

lever

Inhibitor

switch
and
wiring

Vacuum

diaphragm
and
piping

Kick-down
solenoid,
kick-down
switch

and

wiring

Engine

idle

speed

and
condition
Engine
stall

speed

Fluid

pressure
(Line
and
governor)
Control
valves

Governor

valve
Band
servo

Transaxle

air
check
Ignition
switch
and

starter

Front
clutch

Rear

clutch

Brake

band

Low
and

reverse

brake
Oil
pump
Hydraulic
circuit

Torque

converter

One-way

clutch
Parking
linkage

Planetary

gear

Snift
sequence

Shifts from
1st to
2nd
or
2nd
to
3rd
in 1
range

Slipping

Practically
no
shift shock,
or
slip-page while 1st
to
2nd shifting 1
2 •
3
• •
•
4 5
•
7 6
• •
• ©
•
• ©
•
• •
•

Slipping

Pracatically
no
shift shock
or
slip-page while 2nd
to
3rd shifting 1
2 •
3
• •
•
4 5
•
7 6
•

Slipping

No shift shock
or
engine runaway
in 1 to 2
range shift 1
2 •
3
• 4
5
• 6
•
• 7
• •
• ©
•
© •
•
• •
•
Slipping

Engine runaway
or
slip when shifting
3rd to 2nd
1
• •
2
• •
•
3 4
•
5 6
• ®
• ©
•
• ®
•
• •
•

Slipping

Slippage evident when vehicle starts moving 1
2 •
5
• •
•
3 4
•
• 6
• •
• •
•
® ©
•
• •
•

Noise

Transaxle noisy
in P and N
range

Noise
Transaxle noisy
in D, 2, 1 and
R ranges •
(D •
•
© •
•
© •
©

Others

No engine brake
in 1
range •
1 •
•
• •
•
2 3
•
• 4
• •
• •
©
• ©
•
• •
•

Others

Vehicle moves
in P
range
or
parking gear
not
disengaged when
P
range disengaged
•

Others
Transaxle overheats 3
4 5
•
2 6
• ®
©
(D ©
© ©
©
• •
©
Others

White smoke from exhaust while running 1
• •
2
• •
3
4 5
•
• 6
• ®
© ©
©
© ©
©
• •
@

Others

Abnormal odor from
oil
level gauge pipe ©
® ©
©
© ®
©
• •
©
76G07C-016
Differential
Problem Probable Cause Remedy Page
Noise Insufficient fluid Add 7C—25
Low fluid quality Replace with specified
ATF
7C-25
Worn bearing Adjust
or
replace 7C-79
Contact surface
of
gears worn Replace 7C-79
Tooth surface
of
gears damaged Replace 7C-79
Contaminated
ATF
Repair
or
replace 7C-25
Differential gear damaged, excessive backlash Replace 7C-79
Excessive bearing preload Adjust 7C—94
76G07C-017
7C—11

7C REMOVAL
14. Disconnect the tie-rod ends with the SST.
76G07C-061
76G07C-062
76G07C-063
15. Remove the stabilizer bar control links.
16. Remove the bolts and nuts at the left and right low-
er arm ball joints.
17. Pull the lower arms downward to separate them
from the knuckles.
Caution
Do not damage the ball joint dust boots.
18. Separate the left driveshaft from the transaxle by
prying with a bar inserted between the shaft and
the case.
Caution
Do not damage the oil seal.
19. Remove the joint shaft bracket.
20. Separate the right driveshaft together with the joint
shaft in the same manner.
21. Install the SST into the differential side gears.
Caution
Failure to install the SST may allow the
differential side gears to become misaligned.
76G07C-064
7C—32

DISASSEMBLY 7C
5. Assembly the SST.
76G07C-076
76G07C-350
6. Attach the hanger to the oil pump as shown.
7. Lift the transaxle and mount it on the SST.
Warning
Avoid leaning the transaxle to one side dur-
ing disassembly, it may turn quickly and cause
injury.
Note
If troubleshooting indicates that there is a
problem on the differential side, separate the
transaxle case assembly from the converter
housing and cover it.
63U07B-064
8. Remove the inhibitor switch.
76G07C-077
7C—37

DISASSEMBLY 7C
DISASSEMBLY-STEP 4
Component
76G07C-120
76G07C-121
1. Side bearing housing
2. Differential assembly
3. Roll pin
4. Bearing housing
5. Idle gear assembly
6. Output gear assembly
7. Bearing cover
8. Bearing outer race
9. Oil seal
10. Converter housing
7C—51

7C DISASSEMBLY
76G07C-122
76G07C-123
76G07C-124
Procedure
1. Remove the side bearing housing installation bolts
from the transaxle case.
2. Remove the side bearing housing from the trans-
axle case by tapping lightly with a plastic hammer.
3. Remove the differential assembly.
4. Remove the bearing housing.
(1) Remove the bolt indicated in the figure (arrow).
(2) Remove the roll pin with a pin punch.
(3) Remove the bearing housing by tapping light-
ly with a plastic hammer.
76G07C-125
7C-52

INSPECTION AND REPAIR 7C
DIFFERENTIAL
Disassembly
Disassemble in the sequence shown in the figure, referring to the disassembly note for specially marked
parts.
1. Roll pin
2. Side gear
3. Side gear thrust washer
4. Pinion shaft
5. Pinion gear
Dial aauae
76G07C-212
6. Pinion gear thrust washer
7. Side bearing inner race
8. Speedometer drive gear
9. Ring gear and gear case assembly
Disassembly note
Checking backlash
Before disassembly, measure the backlash of the side
gears and pinion gears. If not within specification, re-
place the differential assembly.
Backlash:
Standard 0.025—0.1 mm (0.001—0.004 in)
Maximum 0.5 mm (0.020 in)
86U07B-323
7C-79