ISUZU TF SERIES 2004 Workshop Manual

UNIT REPAIR (AW30–40LE) 7A4–53
OD Support Assembly
Disassembled View
2 52R20 0003
E nd O FCallo ut
Disassembly
1. Check OD brake piston movement.
Place the OD support assembly onto the direct
clutch assembly.
25 2RY 0 0042
Legend
(1) Thrust bearing
(2) Race
(3) Thrust washer (plastic)
(4) Snap ring(5) Piston return spring
(6) OD brake piston
(7) O-ring
(8) Oil seal ring
(9) OD support

7A4–54 UNIT REPAIR (AW30–40LE)
Apply compressed air into the oil passage as
shown, and be sure that the OD brake piston moves
smoothly.
25 2RY 0 004 3
2. Remove the thrust bearing.
3. Remove the race.
4. Remove the thrust washer (plastic).
5. Place special tool on the spring retainer, and
compress the return spring with a shop press.
Spring compressor : J–37233
Remove the snap ring with a screwdriver.
RUW 37A SH00 310 1
6. Romove the piston return spring.7. Place the OD support onto the direct clutch
assembly.
Hold the OD brake piston so it is not slanted and
apply compressed air into the passage to remove
the OD brake piston.
Remove the OD brake piston.
25 2RY 0 0045
8. Remove the O-ring and oil seal rings from OD
support.
Inspection and Repair
Make necessary correction or parts replacement if wear,
damage or any abnormal conditions are found through
inspection.
1. Check piston return spring
Using calipers, measure the free length of the return
spring.
Standard length: 17.2 mm (0.677 in)
25 2RY 0 0046

UNIT REPAIR (AW30–40LE) 7A4–55
Reassembly
1. Coat the two oil seal rings with ATF.
Contract the oil seals as shown, and install them
onto the OD support.
NOTE: Do not spread the ring ends more than
necessary.
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2. Coat two new O-rings with ATF and install them on
the OD brake piston.
3. Being careful not to damage the O-rings, press the
brake piston into the OD support, using both hands.
25 2RY 0 004 8
4. Install piston return spring.
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5. Place special tool on the spring retainer, and
compress the return spring with a shop press.
Spring compressor : J–37233
Install the snap ring with a screwdriver.
Be sure the end gap of the snap ring is not aligned
with cutout portion of the OD support.
RUW3 7A SH00 3201

7A4–56 UNIT REPAIR (AW30–40LE)
6. Coat the thrust washer (plastic) with petroleum jelly
and install it onto the OD support.
NOTE: Make sure that the lug fits into the hole on the
OD support.
25 2RY 0 005 1
7. Coat the race with petroleum jelly, and install it onto
the OD support.
Race diameter (Reference)
25 2RY 0 005 2
8. Turn over OD support.
Coat the two races with petroleum jelly, and install
them onto the OD support.
Race and bearing diameter (Reference)
25 2RY 0 0069
9. Check OD brake piston movement.
Place the OD support assembly onto the direct
clutch assembly.
25 2RY 0 0042
Inside diameter 36.7 mm (1.44 in)
Outside diameter 50.85 mm (2.00 in)
Inside Outside
Race (A) 37.2 mm (1.465 in) 58.8 mm (2.315 in)
Bearing and
race (B)33.7 mm (1.327 in) 50.1 mm (1.972 in)

UNIT REPAIR (AW30–40LE) 7A4–57
Apply compressed air into the oil passage as
shown, and be sure that the OD brake piston moves
smoothly.
25 2RY 0 004 3

7A4–58 UNIT REPAIR (AW30–40LE)
Direct Clutch Assembly (C-2)
Disassembled View
2 48R20 0001
E nd O FCallo ut
Legend
(1) Clutch drum thrust washer (Plastic)
(2) Snap ring
(3) Flange
(4) Plate and disc
Five plates and five discs(5) Snap ring
(6) Piston return spring
(7) Direct clutch drum
(8) Direct clutch piston
(9) O-ring

UNIT REPAIR (AW30–40LE) 7A4–59
Disassembly
Remove direct clutch drum assembly from forward
clutch assembly.
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1. Check piston stroke of direct clutch (C–2).
Place the direct clutch assembly onto the OD
support assembly.
24 8RY 0 002 9
Using a dial indicator, measure the direct clutch
piston stroke by applying and releasing compressed
air (390 – 780 kPa or 57 – 114 psi) as shown.
Pack clearance: 0.4 – 0.7 mm (0.016 – 0.028 in)
RUW3 7A SH00 4901
2. Remove the clutch drum thrust washer (Plastic)
from the rear end of direct clutch.
3. Remove the snap ring from the direct clutch drum.
4. Remove the flange, plates and discs.
5. Place special tool on the spring retainer and
compress the return spring.
Using snap ring pliers, remove the snap ring.
Spring compressor : J–25048
24 8RY 0 0002
6. Remove the piston return spring.

7A4–60 UNIT REPAIR (AW30–40LE)
7. Place the direct clutch drum onto the OD support.
Holding the direct clutch piston by hand, apply
compressed air to the OD support to remove the
direct clutch piston.
Remove the direct clutch piston from direct clutch
drum.
24 8RY 0 003 0
8. Remove two O-rings from piston.
Inspection and Repair
1. Check piston return spring.
Using calipers, measure the free length of the return
spring.
Standard length: 21.3 mm (0.839 in)
24 7RY 0 003 4
2. Check discs.
Using micrometer, measure the thickness of the
discs.
Minimum thickness: 2.04 mm (0.0803 in)
If the thickness is less than the minimum, replace
the disc.
25 2RY 0 0027
3. Check direct clutch piston.
Check that check ball is free by shaking the piston.
Check that the valve does not leak by applying
low-pressure compressed air.
24 8RY 0 0031

UNIT REPAIR (AW30–40LE) 7A4–61
4. Check direct clutch drum bushing.
Using a dial indicator, measure the inside diameter
of the clutch drum bushing.
Maximum inside diameter: 53.99 mm (2.1256 in)
If the inside diamater is greater than the maximum,
replace the clutch drum.
24 8RY 0 003 2
Reassembly
1. Coat new O-rings with ATF and install them on the
direct clutch piston.
2. Install direct clutch piston to direct clutch drum.
Being careful not to damage the O-rings, press in
the direct clutch piston into the clutch drum, using
both hands.
24 8RY 0 003 3
3. Install piston return spring.
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4. Compress piston return spring and install snap ring
in groove.
Place special tool on the spring retainer, and
compress the return spring.
Install the snap ring with snap ring pliers.
Be sure the end gap of the snap ring is not
aligned with the spring retainer claw.
Spring compressor: J–25048
24 8RY 0 0002

7A4–62 UNIT REPAIR (AW30–40LE)
5. Install four plates and four discs.
Install in order : P–D–P–D–P–D–P–D
P : Plate, D : Disc
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6. Install the flange, with the flat side facing downward.
24 8RY 0 003 5
7. Install the snap ring with a screwdriver.
Be sure the end gap of the snap ring is not aligned
with the cutout portion of the direct clutch drum.
24 8RY 0 0036
8. Check piston stroke of direct clutch (C–2).
Place the direct clutch assembly onto the OD
support assembly.
24 8RY 0 0029Using a dial indicator, measure the direct clutch
piston stroke by applying and releasing compressed
air (390 – 780 kPa or 57 – 114 psi) as shown.
Pack clearance: 0.4 – 0.7 mm (0.016 – 0.028 in)
If the piston stroke is not within specification,
replace the discs and recheck the piston stroke.
If the piston stroke is nonstandard, select another
flange.