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Sonnax 77998-03K Transmission Kit, 1-2 or 3-4 Accumulator Piston (.310" Pin

by Sonnax
SKU S74927K
Original price $10.39 - Original price $10.39
Original price
$10.39 - $10.39
Current price $10.39
in stock, ready to be shipped

Delivery time

You will receive your package in 2–5 business days within the contiguous U.S.

Brand: Sonnax

Other Part Number: S74927K

Type: Piston

Manufacturer Warranty: Yes

Items Included: Pinless Accumulator Piston, seals, two steel balls

Manufacturer Part Number: 77998-03K

Material: Aluminum

Universal Fitment: Yes

Vintage Part: No

Performance Part: Yes

200-4R, 4L60, 4L60-E, 4L65-E, 4L70-E

Pinless Accumulator Piston Kit
Part No. 77998-03K

This listing is for (1) Pinless Accumulator Piston

In 200-4R applications, this kit can only be used in the 3-4 accumulator location.

In listed GM units it is common to have poor shift quality, burnt bands or clutches due to accumulator piston wear. Repeated reciprocation of the accumulator piston causes wear at the piston pin bore interface. After this wear reaches a critical point, fluid loss through the piston pin bore cannot be compensated due to lack of pump volume. In addition, the piston can get cocked and gall the accumulator bore due to the pin bore wear or the spring bottoming out. To prevent these conditions in the 1-2 or 3-4 accumulator bores, Sonnax offers pinless accumulator piston kit 77998-03K.

  • Pinless design eliminates the possibility of pin bore leakage and the additional length stabilizes the piston to prevent piston cocking
  • Dual seals stabilize and completely seal the bore and provide a tight seal even after thousands of cycles
  • Steel balls plug existing pin bore in case or cover
  • D-Ring Viton®
  • Pinless Accumulator Piston Aluminum
  • Seal PTFE
  • Steel Ball .312" dia.
  • Steel Ball .236" dia.

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