1988 PONTIAC FIERO Service Repair Manual

700-R4-30 AUTOMATIC TRANSMISSION
ILL.
NO.
62
1
623 625
626
628
630
63
1 632 DESCRIPTION
HOUSING
& SHAFT ASSEMBLY, INPUT
PISTON, 3RD
& 4TH CLUTCH
RING, 3RD
81 4TH CLUTCH APPLY
SPRING ASSEMBLY, 3RD & 4TH CLUTCH
HOUSING, FORWARD CLUTCH
PISTON, FORWARD CLUTCH
SEAL, OVERRUN CLUTCH (INNER
& OUTER)
PISTON, OVERRUN CLUTCH
JH0113-700R4
Figure 130 Overrun Piston - Installed
Figure 13
1 Overrun Clutch Retaining Ring - Installed
- Composition plates for damaged tangs,
delamination, or excessive wear
- Steel plates for damaged tangs, wear, or
heat damage
@ Input sun gear bearing assembly (637) for wear,
flatness or damage
Assemble (Figures 133 and 134)
1. Overrun clutch plates (645) into the input
housing.
- overrun clutch plates are the smallest of the
three sets of plates in the input housing.
- index the plate as shown.
2. Thrust bearing assembly (637) onto the input
clutch hub
- the inside race must face the input housing
hub.
621 HOUSING & SHAFT ASSEMBLY, INPUT
636 SEAL, INPUT HOUSING TO OUTPUT SHAFT
637 BEARING ASSEMBLY, INPUT SUN GEAR
687 SHAFT, OUTPUT
JH0114-700R4
Figure 132 Input Hsg. to Output Shaft Lip Seal
- retain with petrolatum.
3. Align the tangs on the two composition
overrc.,
clutch plates.
Forward Clutch Sprag Assembly
Disassemble (Figure 135)
1.
Forward sprag outer race (644)
2. Overrun clutch hub retaining snap ring (638) and
clutch hub (639)
3. Forward clutch retainer and race assembly (641)
Inspect
@ Forward clutch sprag assembly (642) for
- wear or damage
- weak or broken springs
- damaged or missing retainer caps (brass)
@ Overrun clutch hub (639) for
- spline damage
- plugged lubrication holes
- damaged tangs
- cracks
o Forward clutch retainer and race assembly (641)
for
- spline damage
- ring groove damage
- surface finish damage
- loose retainer
o Forward sprag outer race (644) for
- spline damage

AUTOMATIC TRANSMISSION 700.R4-31
OVERRUN
*ALIGN WIDE NOTCHES TO CASE LUGS
I OVERRUN CLUTCH I
I I Figure 133 Overrun Clutch Plate Chart
621 HOUSING
& SHAFT
ASSEMBLY, INPUT
637 BEARING
ASSEMBLY, INPUT SUN GEAR
658 GEAR, INPUT SUN
Figure 134 Input Sun Gear Thrust Bearing 641
RETAINER & RACE ASSEMBLY, SPRAG
642 FORWARD SPRAG ASSEMBLY
INER RINGS, SPRAG ASSEMBLY
FORWARD CL -
Figure 135 Forward Clutch Sprag Assembly
- surface finish damage
- plugged lubrication holes
Assemble (Figures 136,137,138)
1. Forward clutch sprag assembly (642) into the
outer race
- to correctly install, the notches in the sprag
cage must face upward as shown.
2. One sprag retainer ring (643) onto the race and
retainer assembly
- the flange on the retainer ring must face
away from the retainer.
3. Race and retainer assembly into the sprag
assembly
- to assemble, hold the outer race in your left
hand with your fingers supporting the sprag
at the recessed side of the outer race.
- insert the race and retainer assembly by
pushing in and turning to the left.
4. The remaining retainer ring onto the sprag
assembly
5. Overrun
clutch hub (639) onto the wear plate
6. Overrun
clutch hub retaining snap ring (638) into
the snap ring groove of the race and retainer
assembly
7. Test the assembly for proper operation as shown.
- If the assembly operates backwards, you
have installed the sprag backwards.
Reassemble correctly.
Assemble
e Forward clutch sprag assembly into the input
clutch housing
- index the overrun clutch hub into the
overrun clutch plates.
Inspect (figure 139 and 140) -
Forward (649) and 3-4 clutch plates (654)
- Composition plates for damaged tangs,
delamination, or wear

700-R4-32 AUTOMATIC TRANSMISSION
A RECESSED FACE
B NOTCHES POINT UPWARD AS SHOWN
C LIPPED EDGE
642 FORWARD SPRAG ASSEMBLY
644 RACE, FORWARD CLUTCH
- OUTER
Figure 136 Sprag Assembly Procedure
COUNTERCLOCKWISE
641
RETAlNER&RACEASSEMBLY,SPRAG 642 FORWARD SPRAG ASSEMBLY
INER RINGS, SPRAG ASSEMBLY
FORWARD CL -
Figure 137 Sprag Race and Retainer Assembly
Procedure
THE OVERRUN'CLUTCH HUB MUST TURN '
I CLOCKWISE, BUT NOT COUNTERCLOCKWISE I
639 HUB, OVERRUN CL
644 RACE, FORWARD CL - OUTER JH0120-700R4
Figure 138 Check Sprag for Proper Operation
- Steel plates for damaged tangs, wear, or
heat damage
e Forward (650) and 3-4 clutch backing plates
(655) for
- flatness
- surface finish damage
- burrs or nicks
Forward clutch apply plate (646) and spacer plate
(647) for
- flatness
- surface finish damage
- burrs or nicks
@ The 3-4 clutch apply plate (653) for
- flatness
- surface finish damage
o The 3-4 clutch ring retainer plate (652) for
- bent tangs
- flatness
Assemble (Figures 139, 140, 141 and 142)
1. Forward clutch apply plate (646) into the input
clutch housing
- index as shown.
2. Waved steel forward clutch plate (648) into the
input clutch housing
- index as shown.
3. The
remaining forward clutch plates (649) into
the input clutch housing
- start with steel plate and alternate with a
composition
4. Forward clutch selective backing plate (650)
5. Forward clutch retaining ring (651)
Forward Clutch Piston Travel Check
Measure (Figure 142)
Check the end clearance between the backing
plate (650) and the retaining ring (65 1) with two
feeler gages.
Select the proper backing plate from the chart to
obtain the correct clearance
Assemble (Figure 143 and 147)
1. The 3-4 ring retainer plate (652)
- index each leg into the apply ring legs.
2. The 3-4 clutch apply plate (653)
3. The
3-4 clutch plates (654)
- start with composition and alternate with
steel
4. The 3-4 boost springs (600) (some models only)
5. The
3-4 clutch backing plate (655) and retainer
ring (656)
- chamfered side up.
3-4 Clutch Piston Travel Check
Measure (Figure 144)
e Check the end clearance between the backing
plate (655) and the first composition plate with
a
feeler gage.

I *ALIGN WIDE NOTCHES TO CASE LUGS (
Select the proper backing plate from the chart to
obtain the correct clearance.
Clutch Air Check
(Figure 145)
Air check the 3-4, forward, and overrun clutches
by applying air pressure at the feed holes in the turbine
shaft. (When the overrun clutch is checked, the air will
blow by the forward clutch piston lip seals and exit out
the forward clutch feed hole in the turbine shaft.)
Assemble (Figure 146)
TOOLS REQUIRED:
J-36418- 1 seal installer
J-36418-2A seal sizer
1. Install four turbine
shaft oil seal rings (619) using
J-36418-1
- Adjust screw to obtain proper height
2. Use
J-36418-2A to size the seals after installation
Reverse Input Clutch Assembly
+++ Disassemble (Figure 148 and 149) [I]
TOOLS REQUIRED:
J-23327 Clutch Spring Compressor
J-25018 Clutch Spring Compressor
Adaptor
1. Retaining
ring (614) from reverse input housing
2. Backing plate (613)
3. Clutch plates (612) and belleville steel plate (61 1)
AUTOMATIC TRANSMISSION 700-R4-33
ILL.
NO. DESCRIPTION
621 HOUSING & SHAFT ASSEMBLY, INPUT
646 PLATE, FORWARD CLUTCH APPLY
648 PLATE, FORWARD CLUTCH (WAVED)
649 PLATE ASSEMBLY, FORWARD CLUTCH
650 PLATE, FORWARD CLUTCH BACKING
(SELECTIVE)
651 RING, FORWARD CLUTCH BACKING PLATE
RETAINER
652 PLATE, 3RD
& 4TH CLUTCH RING RETAINE 653 PLATE, 3RD & 4TH CLUTCH APPLY (STEPPED) 654 PLATE ASSEMBLY, 3RD & 4TH CLUTCH
655 PLATE, 3RD & 4TH CLUTCH BACKING
(SELECTIVE)
656 RING, 3RD
& 4TH CLUTCH BACKING

700-R4.34 AUTOMATIC TRANSMISSION
FORWARD CLUTCH INFORMAT ION CHART
THICK.
ALL MODELS
COMPOSITION
FACED CLUTCH
Figure 14 I Forward Clutch Plate Chart
4. Install J-23327 and J-25018.
- compress the spring assembly.
5. Spring assembly retainer ring (610) and spring
assembly (609)
6. Reverse
input clutch piston (607)
- inner and outer lip seals (608) from piston
Inspect (Figures 148 and 150)
e Backing plate (613) for
- damage
- distortion or flatness
- burrs or surface finish damage
Clutch Plates (612)
- Composition for tang damage,
delamination, or wear
- Steel for tang damage, wear, or heat damage
o Spring assembly (609) for distortion or damage
o Piston (607) for
- poposity
- damaged lip seals
o Housing and drum assembly (605) for
- damaged or worn bushings (603 and 606)
- surface on the hub and outer housing
- leak at the weld
Assemble (Figures 148, 1 49, 151, 152 and 152A)
TOOLS REQUIRED:
5-23327 Clutch Spring Compressor
J-25018 Clutch Spring Compressor
Adaptor
1. Inner and outer seals (608) on the piston
- lips must face away from the hub as shown.
- lubricate with transmission fluid.
2. Piston (607) into the housing and drum assembly
- use an 8 mm feeler gage to position the lip
seals.
FORWARD CLUTCH BACKING PLATE SELECTION
I ALL MODELS
BACKING PLATE TRAVEL =':,~~,--'~~$~
621 HOUSING & SHAFT ASSEMBLY, INPUT
650 PLATE, FORWARD CLUTCH BACKING
651 RING, FORWARD CLUTCH BACKING PLATE
RETAINER
JH0124-700R4
Figure 142 Forward Clutch Backing Plate Travel
- use care not to damage the seals.
3. Spring assembly (609)
- large opening in the assembly goes towards
the piston.
4. Install J-23327 and
J-25018.
- compress the spring assembly
- install the retainer ring (610).
5. Belleville steel
clutch plate (61 1)
6. Clutch
plates (612).
(4 steel and 4 composition
plates required)
- start with a composition and alternate with
steel
7. Backing plate (613)
- chamfered side up
8. Retaining ring (614)
Measure (Figure 151,152,152A and 153)
1. With the Reverse Input Clutch fully assembled,
apply an evenly distributed load to the Clutch
Pack in the direction shown in Figure
1. Medium
pressure (approximately 20 lbs.) on the Backing
Plate applied by hand on five evenly distributed

AUTOMATIC TRANSMISSION 700.R4-35
3-4 CLUTCH
INFORMATION CHART
PLATE TYPE THICK- / NESS
FLAT STEEL 11.97mml 6 15 1
CLUTCH
PLATE (.077")
COMPOSITION I 1 1 1
FACED CLUTCH ~:~~~~
PLATES
STEPPED
tSAME SPLINE CONFIGURATION AS APPLY PLATE
" A-MODELS
Figure 143 3-4 Clutch Plate Chart
FAM,
FMM, MAM, MFM, MRM,
MXM, MCM, MTM, PRM, TAM,
TBM, YXM
points will obtain the Backing Plate Travel for
measurement.
CAUTION: (Excessive pressure will
distort the
Belleville plate resulting in
an inaccurate measurement.)
2. Using a Feeler Gage, measure between the Snap
Ring and the Backing Plate. Backing Plate Travel
should be
1.02mm - 1.94mm (.040" - .076").
3. Select the proper Backing Plate to obtain the
specified travel.
Reverse lnput and Input Clutches
Assemble (Figures
154 and 155)
1. Selective thrust washer (616) onto the input
housing
2. Bearing assembly (6 15)
- inside (black race) goes toward the oil
Pump.
3. Reverse input clutch assembly (605) onto the
input clutch assembly
- index the reverse input clutch plates with
the input clutch hub.
- make certain all clutches are fully engaged.
Assemble (Figure 156)
a Reverse input and input clutch assembly into the
transmission case
- index the 3-4 clutch plates with the input
internal gear.
I 3-4 BACKING PLATE SELECTION I
BACKING PLATE
'ODE' I TRAVEL
FAM,FMM,MAM,MFM, 2,42mm . 1,61mm MRM,MXM,MCM,MTM, 1,095,, - .063 ,,, PRM, TAM, TBM, YXM
ALL OTHERS
2.40mm - 1.52mm
1.094" - .060")
621 HOUSING & SHAFT ASSEMBLY, INPUT
654 PLATE ASSEMBLY, 3RD & 4TH CLUTCH
655 PLATE, 3RD & 4TH CLUTCH BACKING ~~0126-700~4
Figure 144 Backing Plate Selection Chart
- make sure all clutch plates are fully
engaged.
- when properly assembled, the reverse input
clutch housing will be located just below the
case oil pump face.
2-4 Band Assembly
a 2-4 band assembly (602) for damage or wear
Assemble (Figure 156, 157)
1. The
2-4 band assembly (602) into the case
- index the band anchor pin end with the case
pin hole.
2. Band
anchor pin (48) into the case
- index the pin into the 2-4 band.

700-R4-36 AUTOMATIC TRANSMISSION
619 RING, OIL SEAL (TURBINE 621 HOUSING & SHAFT ASSE
JH0128-700R4
2. OVERRUN CLUTCH 4. 3 -4 CLUTCH
3. FORWARD CLUTCH
Figure
145 Turbine Shaft Oil Passages
Figure
146 Turbine Shaft Oil Seal Rings
Oil Pump Assembly
Remove or Disconnect (Figure 160)
1. Thrust washer (601)
2. Pump cover to case gasket (9)
3. Pump to case oil seal (8)
4. Pump cover bolts (236)
5. Pump cover (217) from pump body (203)
Pump Body
Disassemble (Figure 160)
1. Pump slide spring (209)
- compress with needle nose pliers.
- pull straight out.
CAUTION: Spring is under very high
pressure. Place covering over spring
to prevent possible injury.
2. From the pump pocket
e Pump guide rings (212)
Pump vanes (215)
e Pump rotor (214)
e Pump guide (213)
e Slide (206)
e Slide Seal (21 1)
e Seal Support (210)
e Pivot slide pin (208) and spring (207)
e Slide seal ring (204) and slide back up seal
(205)
3.
Retainer (94), oil seal assembly (2) - pry out with a screwdriver.
Oil Pump Cover
Disassemble (Figure 160)
1.
Converter clutch apply valve train
- compress converter clutch apply valve
spring (228) with a screwdriver.
- remove retaining ring (225). - slowly release the spring tension. - stop valve (226), converter clutch apply
valve
(227), and two converter clutch valve
springs.
2. Pressure relief ball (231)
- ball is under strong spring pressure. - cover the ball with a cloth when removed.
3. Pressure regulator assembly (2 18-224).
- follow the same procedure used to remove
the converter clutch valve.
Inspect (Figure 160)
e Pressure regulator valve assembly (2 18-224) and
converter clutch apply valve assembly (225-229)
for
- chips, burrs, distortion, plugged oil passage,
and free movement in bore
- remove burrs with lapping compound
e Pressure relief assembly (230-232) for damage or
distortion
e Pump cover (217) and pump body (203) for - worn or damaged bushings (see Bushing
Replacement Procedure)
- foreign material or debris
- porosity
- scored or irregular mating faces
- cross channel leaks
- ring groove damage
e Rotor (214) and slide (206) for cracks

AUTOMATIC TRANSMISSION 700-R4-37
600 SPRING ASM., BOOST 3-4 CLUTCH 639 HUB, OVERRUN CLUTCH
61 9 RING, OIL SEAL (TURBINE SHAFT) 641 RETAINER & RACE ASSEMBLY, SPRAG
620 RETAINER & CHECK BALL ASSEMBLY 642 FORWARD SPRAG ASSEMBLY
621 HOUSING
& SHAFT ASSEMBLY, INPUT 643 RETAINER RINGS, SPRAG ASSEMBLY
622 SEAL, "0" RING INPUT TO FORWARD HSG. 644 RACE, FORWARD CLUTCH (OUTER)
623 PISTON, 3RD & 4TH CLUTCH 645 PLATE ASSEMBLY, OVERRUN CLUTCH
624 SEAL, 3RD
& 4TH CL. (INNER & OUTER) (STEEL & COMP.)
625 RING, 3RD
& 4TH CLUTCH APPLY 646
PLATE, FORWARD CLUTCH APPLY
626 SPRING ASSEMBLY, 3RD & 4TH CLUTCH 648 PLATE, FORWARD CLUTCH (WAVED)
628 HOUSING, FORWARD CLUTCH 649
PLATE ASSEMBLY, FORWARD CLUTCH
629 SEAL, FORWARD CLUTCH (INNER
& OUTER) 650 PLATE, FORWARD CLUTCH BACKING (SEL.)
630 PISTON, FORWARD CLUTCH 651
RING, FORWARD CLUTCH BACKING PLATE
631 SEAL, OVERRUN CLUTCH (INNER & OUTER) RETAINER
632 PISTON, OVERRUN CLUTCH 652
PLATE, 3RD & 4TH CLUTCH RING RETAINER
634 SPRING ASSEMBLY, OVERRUN CLUTCH 653 PLATE, 3RD & 4TH CL. APPLY (STEPPED)
635 SNAP RING, OVERRUN CLUTCH SPRING 654 PLATE ASSEMBLY, 3RD & 4TH CLUTCH
RETAINER 655 PLATE, 3RD
& 4TH CLUTCH BACKING (SEL.) 636 SEAL, INPUT HOUSING TO OUTPUT SHAFT 656 RING, 3RD & 4TH CLUTCH BACKING
637 BEARING ASSEMBLY, INPUT SUN GEAR PLATE
RETAINER
638 SNAP RING, OVERRUN CL. HUB RETAINING
~~0129-700~4
Figure 147 Input Clutch Assembly
e Oil seal assembly for damage or wear Pump Body
Clean
e Wash and air dry all parts.
- do not wipe dry with a cloth.
Measure (Figure 159)
TOOL REQUIRED:
One inch Mircormeter
e Oil pump rotor (214) thickness
Oil pump slide (206) thickness
Important Assemble
(Figures 160, 161 and 162)
TOOL REQUIRED:
J-250 16 Seal Installer
1.
"0" ring seal (205) and oil seal ring (204) into the
groove on the back side of the slide
- retain with petrolatum.
2. Pivot
pin spring (207) and pivot pin (208) into the
pump body
3. Slide (206)
- index the notch in the slide with the pivot
pin.
- the oil seal ring must face downward into
the pump pocket.
4. Slide seal
(2 1 1) and support (2 10)
5. Vane guide ring (2 12)
Measurement of
rotor/slide must be made on 6.
Rotor
guide (213) onto the rotor
undamaged surfaces. Select similar size replacements.
- retain with petrolatum.
Lightly hone both sides of replacement rotor or
slide 7. Rotor (214)
to remove any nicks or burrs. - with guide toward the pump pocket.