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.





^ 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 4EX21 (2WD) 1.95 mm (0.007 inch)
Model 4EX01 (4WD) 2.15 mm (0.085 inch)
Retaining plate: Refer to Application and ID.