Low and Reverse Brake

Pre-Inspection




Low and reverse brake operation
1. Apply compressed air through the oil passage as shown.
2. Verify that the retaining plate move toward the snap ring.

Air pressure: 390 kPa (4.0 kgf/sq.cm, 57 psi) max.

3. If not, the D-ring or the seal ring may be damaged or fluid may be leaking at the piston check ball. Inspect and replace as necessary when assembling.




Clearance between retaining plate and snap ring
1. Measure the clearance between the retaining plate and the snap ring.

Clearance: 0.8 - 2.4 mm (0.031 - 0.094 in)

2. Select the correct retaining plate when assembling.




Disassembly / Inspection / Assembly
1. Disassemble in the order shown in the figure, referring to Disassembly Note.
2. Inspect all parts and replace as necessary.
3. Assemble in the reverse order of disassembly, referring to Assembly Procedure.

Disassembly note




Low one-way clutch inner race

CAUTION: Do not allow the spring retainer to jump out when removing the low one-way clutch inner race.
Remove the Alien-head bolts, washers, and low one-way clutch inner race.




Low and reverse brake piston
Remove the low and reverse brake piston by applying compressed air through the oil passage as shown.

Air pressure: 390 kPa (4.0 kgf/sq.cm, 57 psi) max.

Inspection




Drive plates
1. Measure the facing thickness in three places, and calculate the average.

Thickness
Standard: 2.0 mm (0.079 in)
Minimum: 1.8 mm (0.071 in)

2. If not within specification, replace the drive plate.




Return springs
1. Measure the spring free length.




Specification

2. If not within specification, replace the return spring.




Low one-way clutch inner race
1. Apply petroleum jelly to new seal rings and Install them to the one-way clutch inner race.
2. Measure the clearance between each seal ring and ring groove.

Standard clearance: 0.10 - 0.25 mm (0.004 - 0.010 in)
Maximum clearance: 0.25 mm (0.010 in)

3. If not within specification, replace the low one-way clutch inner race.

Assembly procedure




1. Apply ATF to a new D-ring and seal ring and Install them to the low and reverse brake piston.






CAUTION:
- Apply even pressure to the perimeter of the brake piston when Installing it to avoid damaging the D-ring and seal ring.
- If the piston cannot be turned by hand, remove it and check for damage to the seal ring.

2. Apply ATF to the inner face of the transmission case.
3. Install the low and reverse brake piston in the transmission case by turning it evenly and gradually.




4. Set the return springs, spring retainer, and low one-way clutch inner race into the transmission case.




5. Verify that the return springs, spring retainer, and low one-way clutch inner race are properly positioned.




6. Tighten the Alien-head bolts evenly and gradually in the order shown.

Tightening torque: 21 - 26 mm (2.1 - 2.7 kgf.m, 16 - 19 ft.lbf)




7. Install the dished plate as shown.






NOTE:
- Installation order
Driven-Drive-Driven-Drive-Driven-Drive-Driven-Drive-Driven-Drive-Driven-Drive
- Soak new drive plates in ATF for at least two hours before Installation.

8. Apply ATF to the drive plates and driven plates, and Install them into the transmission case.




9. Install the retaining plate.

CAUTION: Do not deform the snap ring.

10. Install the snap ring.




11. Measure the clearance between the retaining plate and the snap ring by using a feeler gauge. If not within specification, adjust the clearance by selecting the correct retaining plate.

Clearance: 0.8 - 2.4 mm (0.031 - 0.094 in)

Reatining Plate Size:

Retaining Plate Size




12. If the clearance cannot be brought to within specification after Installation of the thickest retaining plate, replace the dished plate, driven plates and drive plates.

Adjust the clearance by selecting the correct retaining plate.

Clearance: 0.8 - 1.2 mm (0.031 - 0.047 in)






CAUTION: Apply air for no more than 3 seconds.

13. Verify operation of the piston by applying compressed air through the oil passage of the low and reverse brake as shown.

Air pressure: 390 kPa (4.0 kgf/sq.cm, 57 psi) max.




14. Apply petroleum jelly to the bearing, and Install it on the low one-way clutch inner race with the black surface facing downward.

Bearing outer diameter: 78.1 mm (3.075 in)






CAUTION: Do not overexpand the seal rings when Installing them.

NOTE: Press the seal rings down into the petroleum jelly to hold them.

15. Apply petroleum jelly to the seal rings and Install them onto the low one-way clutch inner race.