Shock absorber having a full displacement valve assembly

A shock absorber comprising:

• a pressure tube forming a working chamber;
• a piston assembly disposed within said pressure tube dividing said working chamber into an upper working chamber and a lower working chamber, said piston assembly comprising:
• a first housing;
• a second housing attached to said first housing;
• a first plurality of passages extending between said upper and lower working chambers, said first plurality of passages extending through said first and second housings;
• a first valve assembly disposed in said upper working chamber adjacent a side of said first housing facing said upper working chamber, said first valve assembly including a first valve disc engaging said first housing to close at least one of said first plurality of passages and a first biasing member generating an asymmetrical load to bias said first valve disc against said first housing;
• a first plurality of lands extending from said side of said first housing, said first valve disc engaging said first plurality of lands, each of said first plurality of lands fully encircling a respective one of said first plurality of passages;
• a second plurality of passages extending between said upper and lower working chambers, said second plurality of passages extending through said first and second housings;
• a second valve assembly disposed in said lower working chamber adjacent a side of said second housing facing said lower working chamber, said second valve assembly including a second valve disc engaging said second housing to close at least one of said second plurality of passages;
• and
• a second plurality of lands extending from said side of said second housing, said second valve disc engaging said second plurality of lands, each of said second plurality of lands fully encircling a respective one of said second plurality of passages.