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Fourth Servo Overhaul




Fourth Servo Overhaul




1. Remove the following parts:

* The 4th servo piston seals (532, 525)
* The snap ring (531)
* The apply pin (527)
* The spring and retainer assembly (533)




2. Inspect the following parts:

* The 4th servo piston (529) for cracks
* The apply pin (527) for damage
* The spring and retainer assembly (533) for damage
* The servo cover (524) for damage




3. Install the following parts:

* The new piston seal (532) onto the 4th servo piston (529)
* The apply pin (527)
* The spring retainer (533) into the 4th servo piston (529)
* Attach the snap ring (531) to the apply pin (527).




4. Install the 4th servo piston assembly (529) and the spring (533) into the 4th servo cover (524).
Apply pipe thread sealant GM P/N 12346004 to bolt threads before installation.
5. Install the 4th servo piston and cover assembly into the case.





Caution: Refer to Fastener Caution (Fastener Caution).

6. Install the 4th servo cover bolts into the case. Hand tighten the bolts while holding the piston compressed, then tighten in a star pattern to 8-14 Nm (6-10 lb ft).