4L60E 4L65E Trans Boost Valve Early Pump .470" o-ring style Sonnax 77898E-4K Rebuild Kit the servo piston is side-loaded

the servo piston is side-loaded in the case

Reduces or eliminates leakage in eroded OE bores

No-noise pump flow control valve assembly

Compress Large OD Spring Retainers

* Provides better holding capacity and longer transmission life

4L60E 4L65E Trans Boost Valve Early Pump .470" o-ring style Sonnax 77898E-4K Rebuild Kit the servo piston is side-loadedBrand: Sonnax Manufacturer Warranty: Yes Fitment Type: Direct Replacement Items Included: Line Pressure Boost Valve Kit Manufacturer Part Number: 77898E 4K Material: Aluminum Universal Fitment: Yes Vintage Part: No Performance Part: Yes 4L60 E, 4L65 E Transmission Pump Boost Valve Kit Part No. 77898E 4K Early pump design, . 470" dia., O ring style with OE ratio GM 4L60 E and 4L65 E transmissions frequently have poor line rise, which can result in 3 4