Forward and Overrun Clutches

DISASSEMBLY AND ASSEMBLY
Forward and overrun clutches are serviced essentially the same way as reverse clutch is serviced. However, note the following exceptions.





- Check of forward clutch operation





- Check of overrun clutch operation
- Removal of forward clutch drum Remove forward clutch drum from transmission case by holding snap ring.





- Removal of forward clutch and overrun clutch pistons





a. While holding overrun clutch piston, gradually apply compressed air to oil hole.





b. Remove overrun clutch from forward clutch.





- Removal and installation of return springs





- Inspection of forward clutch and overrun clutch return springs
Inspection standard: Refer to Specifications; Mechanical.





- Inspection of forward clutch drive plates
Thickness of drive plate:
Standard 1.52 - 1.67 mm (0.0598 - 0.0657 inch)
Wear limit 1.40 mm (0.0551 inch)





- Inspection of overrun clutch drive plates
Thickness of drive plate:
Standard 1.90 - 2.05 mm (0.0748 - 0.0807 inch)
Wear limit 1.80 mm (0.0709 inch)





- Installation of forward clutch piston and overrun clutch piston
a. Install forward clutch piston by turning it slowly and evenly.
- Apply ATF to inner surface of clutch drum.





- Align notch in forward clutch piston with groove in forward clutch drum.





b. Install overrun clutch by turning it slowly and evenly.
- Apply ATF to inner surface of forward clutch piston.





- Measurement of clearance between retaining plate and snap ring of overrun clutch
Specified clearance:
Standard 1.0 - 1.4 mm (0.039 - 0.055 inch)
Allowable limit 2.0 mm (0.079 inch)
Retaining plate: Refer to Application and ID.





- Measurement of clearance between retaining plate and snap ring of forward clutch
Specified clearance:
Standard 0.35 - 0.75 mm (0.0138 - 0.0295 inch)
Allowable limit
Model 4EX16 (2WD) 2.15 mm (0.0846 inch)
Model 4EX17, 4EX23 (4WD) 2.35 mm (0.0925 inch)
Retaining plate: Refer to Application and ID.