Forward and Overrun Clutches
FORWARD AND OVERRUN CLUTCHES
Components
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
While holding overrun clutch piston, gradually apply compressed air to oil hole.
^ 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 - 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.
^ 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: 2.4 mm (0.094 inch)
Retaining plate: Refer to Specifications.
^ 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:
VG33E: Model 4FX17 (2WD) 2.15 mm (0.085 inch)
VG33E: Model 4FX18 (4WD) 2.15 mm (0.085 inch)
VG33ER: Model 4FX19 (2WD) 2.15 mm (0.085 inch)
VG33ER: Model 4FX20 (4WD) 2.35 mm (0.093 inch)
Retaining plate: Refer to Specifications.