Sonnax 4L60/4L60E Input Drum Reinforcement Kit (Sonnax) 77733-51K Heavy Duty High Performance


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SKU (TPD Part#): 77733-51K SNX Categories: ,

Sonnax 4L60/4L60E Input Drum Reinforcement Kit (Sonnax)

The GM 4L60, 4L60-E, 4L65-E and 4L70-E input drum assembly is known to crack and strip out splines where the input shaft is pressed into it (where the overrun piston rides). Sonnax offers a hardened steel sleeve that reinforces the input drum to prevent this failure. Sonnax input drum reinforcement kit 77733-51K includes a custom manufactured overrun piston designed for use only with a stamped steel forward piston, eliminating the need to use aluminum forward pistons.

    Custom overrun piston works with steel forward piston
    Chromoly steel sleeve design will not block clutch feed oil
    Universal design fits both early- and late-model units


    • Reinforcement SleeveOverrun Piston Inner SealOverrun PistonOverrun Piston Outer Seal



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