Accumulator piston for use in vehicle transmission system

An accumulator piston configured to be situated within an accumulator bore of a housing for use in automatic vehicle transmissions, the accumulator piston comprising:

• a cylindrical casing comprising:
• a top surface, a bottom surface opposite the top surface, and a side wall situated between the top surface and the bottom surface;
• a pin guide protruding from the top surface of the cylindrical casing, the pin guide including a centrally disposed aperture, the bore configured to receive an elongated pin;
• and
• a continuous polymer sealing member having a dual-lip design that allows the sealing member to completely encircle and extend over and beneath the side wall of the cylindrical casing such that the sealing member covers any exposed surface of the side wall, the sealing member providing a uniform surface such that the sealing member is configured to prevent misalignment of the accumulator piston within the accumulator bore by maintaining the cylindrical casing in a substantially parallel orientation with respect to the accumulator bore.